The first stable update had few lag issues that would get severe after 48-72 hours of system uptime. The recent update seem to have fixed that. Apps aren't crashing like in few other devices. Battery life is okayish. Losing ~9% per hour while browsing/watching.
Edit: I didn't run any heavy games. So no idea about the performance, battery life or heating performance during heavy gaming sessions.
I am having some problems. First, a widget disappears or get frozen, then I cannot deploy notification shade nor the lock screen appears at all. It is fixed with a simple reboot. However, it is very annoying.