Fast Charging ability is gone after 11 months, full-night-long charges to ~%60
355029
I purchased this almost a year ago. I liked that it was very long. it was very handy when you put on charge while you are laying down on your bed. but the fast charging ability is gone after 11 months. I think that its longevity might have been better.
3333931
I'm updating this to 5 star for two reasons:

1) I was not aware that the battery is user-replaceable, which is a very good design.
2) Customer service is exceptional and exemplary -- they sent me a replacement battery within hours of my review, so they actively monitor consumer  feedback.

Knowing that they stand behind their products (or at least, what the consumers think), I'm far more inclined to purchase future products from this company without the fear of getting stuck with a lemon.

OLD REVIEW:

Hardly a year and the battery no longer charges.  Now I have to plug it in all the time.  Avoid this junk.
4139665
I got this charger one year ago.  Initially it has charged the batteries without any issues. The real issue started only after 10 months. It started displaying the battery status as NULL / not detected / spoiled.  Within a month it spoiled more than 6 batteries in the same way, that includes new batteries(only one month old).  Not sure of the problem, so, switched to another charger, and charged the same spoiled batteries.  This new charger did not find any issue with those spoiled batteries.  Infact, after charging with the new charger,those spoiled batteries are getting charged even with La Crosse Technology Battery charger.

So,  the bottom line is, this La Crosse Technology battery charger showing faulty status.  Unfortunately, before I realized this issue, I threw away 5 perfectly working rechargeable batties into the trash. Now I am out of warranty for this charger.
3996586
Worked good at first...after 1 1/2 months stopped charging altogether.
357990
In less than a year it no longer charges. Guess I got a bad one :(
1116428
lasted for about 4 months.  Now it no longer fast  charges.
1433044
Worked great initially, but then stopped charging after 9 months. Pretty bummed because I love how long and flexible it is, while also charging my devices fast. I got one because of a friend, and hers is still going strong several years later.  Maybe I got a dud?
489884
I am able to charge my S7 phone quickly.
--- uodated on 10jan2018 ---
It stopped working. It does not fast charge anymore. Hope it can be returned
4701941
I bought this in May 2016 and has been working fine until today July 2016. I'm guessing it's not holding its charge because I have connected all night, the red light is on when charging, but when I unplug it and try to turn it on it won't turn on. Very disappointed cause it was working and fit great before this happened.
988164
I bought these batteries at the end of January 2015, everything was going well until this last month (July). The battery that i used today was at 100 percent at noon and had already drained down to 11 percent by 7pm. These batteries barely made it 6 months and i was loving every minute until this passed month. If Anker could replace mine i would greatly appreciate it because i really liked this product until recently.

EDIT: Anker reached out to me and replaced my batteries. Great customer service, very nice people. Happy with the product again.
3651021
This charger worked great for about four months, but has now lost the ability to quick charge my Galaxy S7 Edge.
1629243
Was able to charge several times when fully charged, but it advertises as fast-charging and that is far from accurate.  It can take at least 24  hours to fully charge up, so you may either decide to not wait until it is nearly fully discharged to charge it up, or carry with you an extra smaller charger to use in the meantime, which kind of defeats the purpose of having a powerful charger.
About 5 months and very infrequent use, it became defective, not charging- only one light is on and not blinking. It is not the cord, which works with my other charger.
2784359
What started as a great charger has significantly diminished over the course of 10 months. The quick charge essentially is useless on my Nexus 6 as on the lock screen regularly says "Charging Slowly." It's very prominent now that when using just a music app, let alone navigation, that I lose battery instead of maintaining or gaining.
1000816
It was working well until about a month ago. I started to get pop up notifications that I had 'low battery' when I had the charger pulled in! Then it started to shift back and forth between charging and not charging. Came back from the long holiday to find that it doesn't work at all, and today is exactly the one year mark since I purchased. Hoping the seller will still uphold the one year satisfaction guarantee.
1762463
After about 6-months of usage, I'm in the market for a replacement. The battery was great for about 5-months and now it's about shot. I can charge it to 100% and in about 2-hours it's around 50%. Charging it has also become a nightmare. My phone got down to 1% then did an auto shutdown. It took about 5-hours to a full charge of 100%.
2476451
Does not charge to 100%, Only charges to 70% Then stops
2533158
Worked like gangbusters for 3 weeks.  But, then not so much.  Last night left on charger all night.  Charge was at 54% this morning.  My Samsung Galaxy S7 gets fully charged in just a few hours.  Took my spare phone to work with me, leaving this one on the charger all day.  Upon arrival home, showed 82% charge.  So, essentially sitting on charger for close to 24 hours, it only added 50% charge.  Nice while it lasted.  Will probably toss it and go back to USB plug.