We use a regular Garmin Nuvi. It has only steered us wrong once and that was because 2 roads ran parallel to each other and I took the wrong one. Poor signage did not help the situation. I think you will find that most so called RV GPS units are not that accurate. They are suppose to keep one from getting into situations where the road has overpasses that are lower than the normal 14 feet. From what I have read none of them work very well at doing that. As for accuracy in getting you where you want to go, the Garmin is the best.
Berniece & Russell Johnson
Lil'Bit, a Netherland Dwarf Rabbit
1987 Southwind
1995 Ford F150 Supercab
Life in the fast lane? No thanks, we will stop and smell the flowers at every opportuity