S3 sleep when i'm not using it, unless it's not going to be used for more than 24 hours, in which case it's off and then off at the wall.
S3 sleep uses so little power that i don't see any reason to turn it off completely when i might need to use it soon.
to those that turn off when it's not in use - do you turn off at the wall too? if not, you know that the 5V standby voltage probably uses as much power as S3 sleep anyway?