Having used garmins for about 10 years and the Montana for about a month I have 4 suggestions for simple improvements to the Montana interface:
1) Toggle maps on and off with a single touch to the map name. Don't require going to the enabled/disabled screen.
2) Allow option for the unit to stay on when unplugged, without any user attention. If using a car lighter outlet some cars powerdown the outlet and this turns off the unit unless a key is pressed.
3) Give the option for longer backlight times, like 5 or 10 min. Handy when hands are occupied but need the backlight on but don't want it still on when unattended for long periods.
4) Be able to lock landscape the other direction (180 deg. from current locked landscape position). If using a wrist strap on left wrist, the current locked landscape is upsidedown.
jj