I have the 60Cx and have used it for cycling almost two years. You can download .gpx files from Map My Ride, but it will be a track and not a route. I use City Nav 2009 maps with my unit and started to use BaseCamp, both are Garmin products. Basecamp is free. Aslo check out http://connect.garmin.com/ it will interface with the 60 series units.

I currently use it attached to my backpack, but will be getting a bike mount for my road bike sometime down the road.

If you have any other questions, I'm sure I caused confusion, feel free to contact me.