I'll be using my Garmin Legend on my trip this summer... but I never go anywhere with out a map.
I used the GPS on my drive from Anchorage to Portland OR, on to Fargo, and back up to Anchorage... worked well... gave me actual speed and a trip meter... (something my truck lacks

)
I still don't know if I feel comfortable with it as my only source of direction... but it's a good primary with a map as backup
this is the one I have
I got it for Trail runs in my truck... but I found a good mount for my bike that will "plug" the steering head nut... it's pretty cool