Those are nice units. I got one last summer and used it on the Hot 100 using the turn by turn. Worked great and I use it regularly when cycling. I also recently added the cadence meter and hope to get the heart rate monitor later on.
For the Murfreesboro Bike Club rides I download the .TCX file and upload it to the Garmin basecamp program and then send it to my device. See: http://www.garmin.com/us/products/onthetrail/basecamp
This allows me to pick the route and click start and I'm off!
This site offers some tips / tricks for the Edge 800 as well: http://ridewithgps.com/edge_800