eTrex user here too. Rugged, versatile device. I
plot a tour track with an online mapping service, then down load to the eTrex. Follow the track. Revert to turn-by-turn routing thru a city.
The Garmin Edge series is specifically taylored to cycling and is touch screen activated.
It's an interesting, often useful gadget. Paper maps are more reliable. Any gps map will have errors, and turn-by-turn directions can take you on roads you do not want or need to be on. Proceed with caution.
I consult mine most often to find out how far it is to the nearest town/service.