My original Surface 3 Pro had Simplo battery, it started having battery degradation problem since May 2016. I had been waiting for updates to fix the problem until battery capacity hit 272 mWh, and I couldn't wait any longer so I made an exchange on August 22nd, a few days before my warranty expired. The exchange experience at MS store was painless, although having a non-usable battery for a few months was very very frustrating.
The replacement unit has LG battery. I was happy, because I knew all the problems were from Simplo batteries. I thought I wouldn't have battery issue ever again. However, only a few days later, I was trying to take my Surface to the bedroom, it powered off immediately when I unplugged it from the power cord. I was shocked because the replacement unit was literally brand new, it only had 1 cycle count when I got it, and I had it less than 10 days. Later I plugged back in, the percentage stuck at 92%, and I unplugged it, it powered off. It acted like there was no battery at all.
I packed the Surface 3 Pro the next day, because looking at it made me so angry. Now I'm out of warranty, and I'm not sure the problem can be solved by exchanging to another one, what if a new update causes another problem? I'm still very pissed, how could a company like MS makes such mistakes and let customers suffer for so long? And no official apology thus far? Surface Pro 3 was an delicate and expensive machine, now it's a trouble maker, personally i've lost my faith in MS. I'll keep my Surface 3 Pro in its box, until the issue is totally solved. Who knows how long it's gonna take! Maybe a month, a year or forever?