The feature that creates a round trip would be nice if Garmin routing would really work for bicycle. The one time I used it directed me straight onto the Interstate. After convincing it that I really don't want to bicycle there it routed me through a level B road (which is basically a plowed field, not even gravel just mud). This all is in Iowa where there are an abundance of nice low traffic rural highways. The only useful way is to plot a track beforehand on the computer while doing lot of verifying with paper maps and google street view to check traffic density and road surface.

Not having replaceable batteries is a huge bummer. It's much easier to carry spare AA batteries than a solar charger, generator hookup, etc. Besides you already need these to charge your phone and isn't there a phone app that does "bike" routing too? Google maps comes into my mind.

The only cool thing about that my childhood home is mapped on one of the screen shots.

Of course YMMV as I'm somewhat picky on my routes.