I also bought the TireMinder for our class C. It works great! It's just quiet until one of the tire pressures goes out of the range it's set for, then it beeps at you and flashes a red light.
The rest of the time the screen dims.
Give you a sense of confidence that you can monitor the tires while traveling. I had a blowout on the inside rear of our class c because the valve stem was leaking. With the monitor I could have caught it and switched to the spare. I still carry a tire pressure checker and check them manually at the start of every trip.
Bought it at the CW store.