I really don't understand the need for an auto off feature. I mean, creating an auto off schedule means you know when you want your phone to turn on and off. Why don't you just do it manually then?
That being said, I probably wouldn't use such a feature.
Well, the BB doesn't fully switch off, more like a non alert standby. You can still wake it up of you need to make a call but its not a fully switch off. One thing with the BB is that a full power off (battery out) is a very slow restart (as im guessing with most smartphones these days) so thats why don't do it unless it needs it (an install of new app). The added bonus is the extra power usage i get per charge.
I guess if the iphone 4 is great on battery and it doesn't take long to boot up from scratch then i don't need the auto off option and this case is closed!