Crap, what a nice little unit! Real super light weight, easy to handle. Love the length adjustment design... somebody was thinking. Very easy to assemble out of box. Battery completes a to full charge out of box in about 10-15 mins, so you can plan to use it pretty quick after assembled.So, new battery fully charged, did a small yard in about 15 min, including some edging (nice feature where the head easily spins around), mostly light grass in #1 speed setting, and then a little bit in #2 speed setting for some weedy stuff that got out of hand - knocked the battery down one LED, leaving two remaining. Threw it right back on the charger as recommended when finished and back up to 100% within 10 mins or so. That's a NEW battery, but we all know batteries loose their "umph" after a year or so, depending on usage and other factors.I heavy researched for more than a couple weeks just Googling and comparing makes, models, specs, cost, reviews, etc. and landed on this item. I even found it highly recommended for homeowners by a landscape guy who has a website. It came up as one of the 5 best on one site I visited comparing best bang for buck, and not sacrificing quality. I won't go into the feature set... there is enough info out there, including in these reviews, so do your own research. While my experience is only out of the box, and used twice, I will say this:PROS - Light weight - PERFECT for even a small framed woman to handle. - Super EZ adjustable shaft length is great... combined with easy adjustable handle... I set it for arms straight out, based on my own posture, and I found it very easy to maneuver and maintain an even strut across the lawn. You don't even know the thing is in yours hands... - I like the speed adjustment dial, nice touch to save battery life. Trust me, #1 is all you need for basic grass after mowing - Battery snaps on and off fairly EZ, locks into place with a spring loaded thumb lock. Again another plug for wife's ease of use.CONS - I don't care much for the safety on the trigger. Always need to use thumb or index finger to slide a spring loaded safety switch one way or the other in order to release the trigger. Its not very intuitive, sort of a kludge really. It even feels clunky. But its for safety, so it is what it is. It's probably the only feature I think wifey might not care for. Oh well. - When you spin the head around for edging, there is a metal guide that flips 90 degrees and points down to the ground. Its a nice feature designed to help you maintain an even height against the ground as you move along. The only issue: The guide is designed with spring tension, sort of like a pair of tongs, with each end setting into holes (very much like a handle on a 5 gal bucket); if you are not careful, the very first time you go to flip it forward 90 degrees for edging, it literally digs into the plastic shoulder of the housing it rides on. Real stupid. Too much pressure. My advice - go easy, use both hands on each side and pry it apart a little bit, and THEN snap it 90 degrees. It might pop out completely - not an issue. Its EZ to re-install. I bought two of these, one for my neighbor, and one for us. I assembled both. The first one I learned the hard way. It actually snapped off some of the plastic guide. I don't know, engineers, they can't get anything completely right. It seems like on the return trip, it snaps back fairly well without much issue. I think I might try putting a file to the guide and create some relief so that it doesn't have so much resistance on the initial adjustment.Other than those two issues, it's really a great bang for the buck, I think. I am so done with gas powered tools. I have a professional Husk with the strap and all. What a PIA to use. First off, the thing is a monster, second its not EZ to maneuver, and of course, every year it just gets harder and harder to deal with starting. Gotta pull the carb and rebuild, and clean, and... oh man. Enough already. I used to HATE trimming. Now I'm like... Hey, can't wait to grab the trimmer! Haahaa!Conclusion: I actually bought this with wifey completelyin mind, because she likes to do this stuff. I wanted something she could easily adjust to her dimensions, and just plain EZ to use. This baby fit the bill 100% all around. The feature set offers so much more than I was even looking for. It's a great little machine! Don't hesitate, because when they stop making it, the feature set will be gone. Case in point: We are still using a NOKIA Lumia 920, and Galaxy S5 Actives. These phones are built like tanks, have FAR better features than any of the new junk available, and are still viable in 2017! When something is designed well, you stay with it. I think this trimmer is going to be another Lumia 920 or Galaxy S5 Active...Happy camper! Oh, by the way, the book says 3 YEAR WARRANTY!! NOT 2!! I went and bought the stupid 3 year through Amazon... crap, in 6 years from now, this great model will be no longer available, and we will get stuck with some inferior design. I'm thinking I'll buy another one and just keep it in the box in storage... :-0I have been using the 18V version of this trimmer for about 10-12 years and have been reasonably happy with it. It did not quite have the power of a gas trimmer but it did the job with far less hassle than the gas trimmers we had been using. The biggest drawback to it was the battery consumption. I have an acre property, with about 120 feet of driveway with lawn on both sides. Edging the driveway alone required more than one battery. trimming around the half-acre of fenced backyard and various backyard objects (kids swingset, grill, etc) would require more than one battery. In all we needed 3 batteries to get through all our trimming and edging needs, and sometimes (not often) we would use up all 3 before getting it all done. We had to take care to get the most important parts done first just in case, and go back out after a battery recharge to complete the job.When the 18V batteries began to fail I went looking for replacements and came across this 40V model and based on other reviews I decided to give it a try, and I can say I am extremely happy!The trimmer itself is mostly the same as the 18V model with the exception of the power control. More on that later. It uses the same line spool so I was able to use the line we already had on hand, and save a couple of parts from the spool head of the old model for later use.The two features that really set this apart from the old model are Power and Battery Consumption. Firstly, the POWER: This model easily rivals the gas powered models I have used (admittedly not 'professional' grade models). With the power control set on 3 it gives me enough power to get that really sharp edge on the driveway that the 18V model simply could not. With the power control set to 1 I still have sufficient power to trim around the fence line and other objects. Occasionally I will set it to 2 to get through some weeds or to trim a larger area of grass where the mower doesn't fit.The biggest advantage to me however, is that this model gets through everything I need it to do with just ONE battery, and with power to spare! The power meter on the battery still has 2 of its 3 status lights on when I am done.There are some reviews on the replacement 40V battery which point to the lack of a cut-off circuit on the trimmer to protect the battery, and this is true. The trimmer will not cut off automatically when the battery is low, and this can be a big problem for a Lithium Ion battery of this type since this type of battery will suffer irreparable damage if it is drained below a certain point. Care must be taken not to allow this to occur. As I mentioned previously, this model is able to complete all the work on one battery that the previous model needed 3 to perform, and has power to spare, so the first thing to know is you should ALWAYS recharge the battery after every use, even if you use it only a few minutes. A small charge will not damage this type of battery, there is no 'memory' effect with this battery type. It also is not a problem to leave the battery on the charger between uses.Secondly, keep a careful eye on the battery power meter when using it. There is a small button next to 3 LED lights. Push the button and the lights will indicate the battery state. When only one LED lights, you can still continue to work but check the battery state even more frequently and STOP as soon as no lights come on. Continued use below this battery charge state may cause the battery to fail prematurely. Such failure is likely to be complete, meaning the battery will no longer take any charge at all. This is typical of Lithium Ion batteries and is not a manufacturing fault.Thirdly, use only as much power as you need. The power control has settings of 1-6. The higher the power setting, the lower the runtime you will get from a battery charge. As stated previously I use 3 for edging on my driveway and 1 for regular trimming. I have not had a need to use a setting higher than 3 but I have no thick weeds to trim.Some other reviewers have complained about the string feeder using too much string. This may be true, I have not personally compared the usage with a bump feed trimmer, but I can say the feed mechanism works much more reliably than the bump-feed mechanisms I have used in the past. It is a very simple mechanism, just a single moving part which is replaceable. The cap which holds the spool in place will wear out after a few years. After all it is spinning and does at times accidentally make contact with the ground. It is easily replaceable and is not expensive. I have not found the string usage to be a problem. I think overall, when one compares the cost of the gas+oil plus the bump-feed string usage of a gas powered trimmer with the cost of electricity to charge the battery plus the cost of string, I suspect this model still comes out ahead and it wins hands down in convenience and ease of use.Update 8/30/2017: After a year and almost through our second season with this, I am still very pleased with this product. It still gets the job done on a single battery with power to spare and I've had no issues with it whatsoever.This is the third Black & Decker battery-powered string trimmer that I've owned. I have two ponds where I use it to keep the banks and the back sides trimmed up, as well as fence lines, around trees, and other places that I can't get with a mower. I absolutely love it, EXCEPT that each one has lasted only 2 or 3 years. I'm told by local repair shops that battery-powered trimmers are not worth repairing, so to the landfill they go, which I'm very unhappy about. To be fair, they are worked very hard. And I do think they are excellent tools. The automatic string feeder works like a charm; it has plenty of power (40-amp battery); and the batteries last a LONG time - I still have and use the batteries from my first and second trimmer, and it's very handy to have those charging while I work. So, all in all a great product, but needs to last longer. Otherwise I would give it five stars.The trimmer trims very well on minimum power which supoosedly helps battery run time. Starting with a battery fully charged earlier in the week, it lasted about fourty five minutes; and afterward, recharge to full charge took six hours. All cordless string trimmers should come with two batteries. A second 40 volt 2.0 Ah battery for this one unfortunately is $96 but cannot be shipped to me in Hawaii as the battery is a lithium-ion battery which is prohibited from shipping except with special handling to a retailer for inventory purposes. No retailer here carries the 40 volt 2.0 Ah battery. When shopping for a B&D trimmer, look for the 20 volt trimmer that is available with two batteries (LTSE525).I am overall very satisfied with this purchase and certainly recommend it with one caveat.Pro:- Light weight and well balanced.- Self feed trimmer wire during operation.- Easy to replace trim wire.- Quick charging battery.- Trigger operation helping to extend working time.Con:- Battery drains quickly. Even while cutting at half speed (3/6), I could get no more than 10 to 12 minutes on a battery charge. I got to 15 minutes on the lowest setting (1/6 speed). However, even at minimum speed it still managed to cut soft stem weeds but higher speed is required (3/6 and 4/6) for denser or pack together weeds and grass.Overall:- Battery drain is a concern with all makes so, considering the price, usability and features this is a very good buy.We liked this product until the gearboxand Spindle needed to be replaced and it says this will cost 11 dollars and then as one read further..it says this part is no longer availabel..what a rip off.we need the part as paying 225 dollars and in less that a year No parts ..that should be a signal to everyine DO NOT BUY THIS>and it is probably only good if it works for a few months on a little condo yard..we are careful of our tools and we need the part..so will keep looking and then will try to get our money back?/so dont buy this at all what a mess to be in in the middle of a nice summer in our garden.thx from Elizabeth in alberta.. ps since i got so cross..I found a replacement part for the gear box assembly for this string trimmer at Replacement parts in the USA and it is 14.95 in US dollars..so we are pleased to find this...but it should be right as they give the item number which replaces the number we have.so wish us luck seems there are better trimmers under the brand of Sthil and they seem to have better parts available a feeling better customer !!!...PS AGAIN NOW THE COST TO GET A 14 DOLLAR PART TO cANADA UIS GOING TO BE WITH POSTAGE ABT 60 CDN$ SO WE ARE HAVING OUR SON IN THE usa BUY IT AND MAIL IT TO US..SO THE SAGA OF A 14 DOLLAR PART GOES ON..When I purchased this I didn't expect much as I have a large rural property that requires a lot of trimming around large stones , trees walkways etc. Well call me impressed! This baby chews through everything! I only place it on level 2.5 power level and never an issue. If you have a very large property like I do I would suggest obtaining an additional battery to reduce your down time. Compared to other "brands" this baby is a stealWhen I first bought this I was very excited to use it. It was very quiet and did a great job, even bought another battery so I did would always have a spare in case I needed one. After 2 summers of using it for only about 1/2 hour every week for 2 months it stopped working. It started by making this weird high pitch noise and then stopped spinning completely. When I opened it up I found that all the gears were plastic and the had gotten so hot that they melted together. Now the warranty is expired and I am left with two batteries and a broken trimmer. Would not recommend getting this unless you want to replace your trimmer every 2 summers.I have only used this trimmer a few times but so far have been impressed by its performance. We have an acreage and already own a gas trimmer but I don't like using it as its heavy and awkward. The Black and Decker unit is a nice weight and the battery last long enough for me to trim around the house and flower beds etc.(hubby can use the gas trimmer for the longer jobs). Battery recharges quite quickly but so far the one charge has lasted long enough for what I need. The only reason I'm giving 4 stars is I haven't owned it long enough to see how it will stand up.