I have the Garmin RV 760 LMT and love it. I have it mounted on the curve above the speedometer. I never have to look down. One time it told me to take the trucker's lane on a freeway interchange. I couldn't figure out why. That is, until I looked to my left and saw the low overpass that the regular drivers were using.
You put in the length, width, height, and GVWR (for going over bridges) and it avoids places where your RV can't go.
Added: HWH Kick-Down Leveler; RoadMaster Anti-sway bars; Tornado Rotary Tank Rinser; Accede Backup Sensor Kit; cylinder locks (w/one combo lock); custom sink cover; Kenwood DDX 5706S front radio; Pioneer MVH-X5560BT rear radio; Oxygenics Shower head; ScanGuage II; Blue Ox Tow Bar w/RVi Brake 2; Winegard Rayzar Automatic TV antenna; Trimark Steel door lock; Dometic 310 toilet; whatever is next.