Better yet are humidity sensor switches with a manual On/automatic Off for
odors.
Timers are great for bathroom heaters.
Here's my switch bank. From the left:
Dimmer for the lights
Humidity sensor for the fan*
Timer for the heater.**
* The fan can be turned on manually, but will turn off automatically after 30
minutes, assuming the humidity level is low enough. "Forgetting" is not an
issue.
** The heater can only be turned on via one of the timer switches, but can
be turned off manually if desired. Again, "forgetting" is not an issue.
http://i.imgur.com/HjzkETf.jpg