I have been using a garmin 276c for two years and I like it a lot.
It has a bright clear screen. Its nice if you are out on the trail when the sun goes down. I have had no too cold issues with it.
I bought the auto navigation kit ( 010-10510-00) which has detailed street maps for North America, power adapter, mounts and memory.
I bought the trail software from gpsquebec.ca. I can plan my trips turn by turn and don't have to worry about looking for signs as much (especially at night). I mostly saddlebag and it can be frustrating at intersections with no signs (especially at night).
Good luck with your purchase.