I'm in the Apple Store and all the display model iPad Pros are on iOS 10. All are plugged in, but are constantly complaining the battery is low.
One is at 8% (plugged in) with 5 1/2 hours of usage.
Another shut itself off and showed the charging icon while actually charging.
Yeah but they have been broken by consumers messing with them lol who knows what's on and running... Plus the demo they run when idle. I wouldn't go by that, but it is interesting