I have a replacement SP2 that I am putting through its paces before I send the old one back. It has been fine, but it still seems to exhibit some of the anomalies of my original unit. Specifically, the battery level will spontaneously drop from 25.0% to 21.9%. Since both machines exhibit his same behavior, I am will to chalk it up to weirdness by design. So, I decided to perform the Feb update. I first did a system refresh with the modified image (Jan drivers and 3368 display drivers) - I wanted to make sure that it worked while I had both Surfaces in my possession. After the refresh, I performed a windows update and all the updates successfully installed (including the firmware). And now for the really weird part. Since this new update is supposed to improve the battery reporting, I decided to see what happens when it hits 25%. Sure enough, it dropped to 21.9% as it always had. But, then it dropped again to about 15% at which point, over the next minute, it crept back up to about 21.3%. It then seemed to discharge normally. Hmmm.... Just a I am writing this, I noticed the the battery was at 14.0% and the it again started to climb to 16.3%. I actually logged this behavior with hwinfo. Now it dropped to 10% (giving me the battery warning) and bounced back to 16%. This is really strange. And now down to 9% and back up to 15%. EDIT: I just restarted and the "yoyoing" seems to have stopped for now.... Drat.. never mind... just dropped to 6% and went into hibernation. Perhaps I will try the update on my old unit to see if it does the same thing. I also wonder if it finally fixes the the battery resetting to 100% (which was the main reason for requesting the replacement).