While I have been using DeLorme for over 10 yrs (long before Bus Ownership) I am currently also using my Garmin Nuvi 650. I find the Garmin easier to move about from the Coach to the Toad or any other vehicle, or even when in a new to me Shopping Mall (to return to my car without a 10 mile hike through a parking lot!!!) This said, the Garmin has not proved to be as user friendly as the Delorme to plan and program a trip. The Delorme is really easier , though that could be from the length of time I have been using it. Downside of Delorme is I use it with my laptop which proves to be a bit cumbersome, but larger map/etc makes it that much easier to use also. Given that, upgrades to DeLorme are only new purchases of their CD's available in many stores and via Internet purchase, whereas Garmin is a simple download off the internet. The Delorme handheld device is really pretty good, albeit almost too small to be able to see... where your s'posed to be going. Good hunting