I like to use the hibernate state when I put my Pro 3 into my bag for long periods of time, rather than just using the sleep state by closing the type cover. But I'm not really sure how long to wait after selecting hibernate before closing the type cover. If it's still in the hibernation process, I don't want it to just go to sleep because I've closed the type cover. I've been waiting until the type cover backlight goes out, any ideas how long I should really have to wait?