Don't be scared to run with the performance governor - I do at all times and my tablet has very long battery duration and is in perfect health.
I've modified Slidelock (it's in python so it's easy to change) so that each time I open the sliding keyboard it goes in performance mode, and when I close it, goes back to ondemand. So, less battery draining when I don't use it. The thread is here http://talk.maemo.org/showthread.php?p=295759