I am getting horrible life on my 7+. Installed around lunch yesterday. Seems OK in standby, but with screen on draining fast. I normally listen to google play music and read articles on facebook from the time I get up till I get in the office ~2 hours later. Normally I am around 85% when I get in. Today I was at 53%. I will be resetting to see if it helps.
Installed PB3 on my iPhone 6S+ yesterday and have seen no significant battery difference. I'll admit to being a moderate user so this may make a difference. Even lighter on the iphone 6S+ as I'm using it strictly to play around with IOS 11, it doesn't even have a sim card in it.