I have tried virtually every type of stone guard available and there is only one IMHO that works for both the camper AND the vehicle;
The large rear mudflaps on the vehicle create as many problems as they solve (raise diff temps, raise tyre temps, flick rocks up if flap too low, let rocks thru if flap too high etc...)
The camper mounted deflectors can be good for protecting the camper (depends on the design) but they all seem to be good at deflecting rocks back at the vehicle, so while the camper is protected the vehicle is not.
The StonerStomper is the only one I have found that protects both the camper and the vehicle. My camper has a good rock deflector plus mudflaps underneath, but I still required a stonestomper to look after the vehicle. It has the added bonus of keeping the drawbar free of any rocks too.
Access to the rear of the vehicle is easily maintained, either just lean into the elastic straps or unclip them, only takes a second to do so.
I have no affliation with Stonestomper, just a very happy customer
Cheers
Captain