I have had three original OEM/Canon LP-E6 batteries..well, 2 and one LP-E6N (the 7D 2 battery). In that time, I have purchased 3 extra batteries for each camera body I've owned (I use a battery grip on my cameras: one extra set).... so a total of 9 extra LP-E6 batteries, all from Sterlingtek. I've purchased them directly from Sterlingtek and from Amazon.
I've only had one problem..... I had a defective battery in the bunch I bought for the 7D2: one of them wouldn't charge above 75%. I contacted Amazon and they credited me the amount of the purchase and I immediately bought a replacement.
A day or so later, I got an email from Sterlingtek, noting that I had a defective battery and informing me they were sending me a replacement. I emailed them back to tell them Amazon had already corrected the problem. They emailed me back and said they were sending me another battery anyway and apologizing profusely for the bad cell. It was a pleasure seeing that level of customer service.
Now for performance. So far, two of the Canon batteries lost one bar on the battery level/performance page. All of the Sterlingteks still show the same recharge performance as they did when new. Not bad for a $13.00 battery.
Kim (the male variety) Canon 1DX2 | 1D IV | 16-35 f/4 IS | 24-105 f/4 IS | 100L IS macro | 70-200mm f/2.8L IS II | 100-400Lii | 50 f/1.8 STM | Canon 1.4X III
RRS tripod and monopod | 580EXII | Cinch 1 & Loop 3 Special Edition | Editing Encouraged