I have a Garmin Zumo 220, I got it last Christmas.
I like it. It can be used in my car, bike and when I go overnight to downtown Chicago I like to walk around. Its nice to be sure I can get back to my hotel without getting lost or having to use a taxi.
It fits in my pocket and is easier to carry around than large maps. Now I do like maps at home for planing the general way I wish to go. Buy when out, I prefer a gps.
My Zumo is nice because it works in many different modes. Riding, driving and walking.
Mine was new and onsale for $299 plus about $10 for shipping. The larger screens are less pocketable due to the screen size. On my bike I can tilt the unit in any direction, if the sun is a issue.
Just my thoughts and experience so far.
Goldwing 1500se '98
VN500 LTD '07 Sold