I always hibernate. It's much faster that way. To say the truth, I have problems with some applications, sometimes. Anyway, I always turn the wireless off to avoid problems. Weird problems that you may also have: CPU throttling problems on some apps (Speedswitch xp had that, but i don't use it anymore) and media problems (Windows showing errors if you take the CD/DVD from the drive after the hibernation process has started).
Anyway, all these (mine, at least) problems are solved with a simple logoff => logon (no need for reboot). Since these problems happen rarely with me, I guess the time saved is worth it.
edit: first voter!