I’ve found the Garmin eTrex Touch pretty useful on my long distance trips, and I love the touch interface, but the unit is a real pain to use in the rain, even if I’m not interacting with it. I’ve found that the unit will think I’m tapping the screen to navigate through things like menus and settings, when I’m really not – the unit is just being jostled in my pack.
This video goes over a few simple steps to mitigate this problem.