We have the RV760 and I love it as a gps. It HAS routed us around problems, though I'd never depend on it 100%. We've already had several instances where we had to divert from the programmed route and it gave us the "insufficient RV information" warning, so that wasn't much help. However, pretty much anywhere I see an 18 wheeler I know my 13'6" tall rig will fit.??
I use TireTraker TPMS pressure/temp sensors and have been very pleased so far. With tires being a weakness for RVs, sensors are a cheap warning signal regardless of the brand you choose to use.