No reason that won't work. I use Lowrance M68/GPS as a bow mount on my boat and then in a portable back for ice. It's great, all the way points I mark in the boat I can now walk/drive right to. Even though I'm pretty practiced at lining up the flagpole, the edge of the blue house and that huge tree this is way better.
When I get the time I'll rig the HDS5 with Lake Insight/Hotspot maps if I want to go exploring. I've just got too much info stored on the other to get too far away from that.
