On 10.7.4, my Mac wouldn't restart properly when there are external hard drives connected and mounted. It will stay stuck on the grey screen, and when I press the power button, it returns me to the login screen without rebooting or shutting down.
The "Reopen windows when logging back in" settings is still crap. It actually remembers your last setting prior to a restart/reboot. So if you happen to check the option before that, it will stay checked on your next restart/reboot until it is unchecked again. It is not permanently unchecked for every restart/rebooting.
End up CCC'ed Lion to an external partition and Time Machined SL back to my primary drive.