Just got my 6P! My first run has been decent, 3.5 hrs SOT over 17 hours with 25% left. That's with everything on except for Bluetooth, 50% auto brightness, and location services on high accuracy. It's not as good as the Droid Turbo 2 I ditched for this phone but very acceptable.
I have a couple of questions though: Since the phone wasn't new, does battery life have to settle in again after just a factory reset? I'm hoping so since while the battery life I got was decent, it isn't as good as some of the others I've seen in this forum. Also, for some reason the battery drained noticeably faster when downloading over WiFi (restoring my media from cloud storage). Has anyone else noticed this?