I have had a number of GPS units from a number of manufactures. By far the best was a unit from Lowrance but they got out of the land GPS business. Rand Mcnalley was the worst. I really liked the Garmin Street Pilot but, like most things I like, the company no longer makes them. I currently have a Garmin LMT760 RV and it is one of the better I have had. Large screen and mostly easy to use. I don't use the RV setting because it doesn't seem to know anything about where I am going and I don't like the pop up telling me that. Since I no longer drive a truck cross country the ability to easily see at a glance my entire two week itinerary isn't quite as important. Both the Lowrance and the Street Pilot excelled at that.
I made my own mount because the suction cup mount was unreliable.