Need advice on an RV GPS?

I used to sing the praises of our Garmin RV760LMT... until we hit the road full-time. In RV mode, it has - or would have - taken us on some really "whack" routes. I assume this is because it thinks doing things like taking propane through the I-95 tunnel through downtown Baltimore or driving through downtown Richmond, Houston, and other major cities is a good idea just because I'm pulling an RV. Like someone said above, I've gone back to a mix of old-fashioned navigation and Google maps. In "car mode," the RV760 is still very handy... it matched the route I chose on our last travel day and has very good "Up Ahead" functions for fuel, etc. Once the GPS and I agree on the route, it's very handy for telling me how far to the next turn, how exits are configured, and our ETA at our final destination. The days are gone, however, when I will just accept that Garmin knows best as far as a route that makes sense for me and my rig.