The battery issues are, oddly enough, specifically regarding idle use - the phone fails to disable wifi when going to sleep and sometimes interrupt handlers that run while the phone is asleep cause it to wake up and peg a core at 100% utilization, killing the battery.

The phone's battery usage while not asleep is actually quite good! And if you disable WiFi, it's less likely you'll hit the bug. But it still happens to me a few times a day, so I have to charge it daily even if I'm not using it - and that's frustrating.