I just bought the Rand McNally 5510 and still learning to use it, it has a ton of RV features and single tap on the screen next exit feature for the interstates but since I have not used an interstate since I got it I cant coment on how usefull that is.
Like most trucker Gps's you program, your length, height weight etc, so it will not take you under bridges that are too low, (in theory), One great feature is the verbal and viual speed limit warning, the MPH digits on my Canadian RAM Odometer are tiny compared to the KMPH digits and with sunglasses are invisible, this is very useful.
I originally had the WorldNav 5200 which I sent back for a refund it gave endless problems and all though they claim it is for RVs it is not. The Rand though is clearly built for RVs, time will tell, but so far I am very impressed. Camping World members price $319.
Nigel & Bev
Brit Driver & Canadian Naviguesser
2011 Rockwood Signature Ultra Lite 8280ws
2011 Dodge Ram 3500 4x4 Diesel