The RIB system uses proportional braking pressure so it can't over brake, my BlueOx portable used to lock up the cars brakes once in awhile at low speed, why I switched. I can set how much pressure is applied to the pedal, you want just enough braking to offset the toad's weight, no more. Best way to set it is to use an empty parking lot and measure normal stopping distance without the toad from say 30 mph, then adjust pedal pressure to stop in the same distance with the toad connected. This way the toad will not push or drag on your RV. I have towed a car for many thousands of miles and the Roadmaster system is the best, harder to install, but once installed hookup is just plugging in the tow lights. The roadmaster system is designed to power your booster so you have your power brakes working normally without undue pressure being applied, not sure if it can work without the vacuum line connected.I use the RVI system, love it. On vacuum systems you cycle 3 times to burn off vacuum. On electric systems you're good because booster does not run unless ignition is on.