Since you have a gasser the first question you need to decide is "permanently installed or portable?".
I use a Demco Stay-IN-Play DUO with an Equinox, which is permanently installed. Hook up the tow bar electrical cable, flip a switch inside and you're ready to go. The Stay-IN-Play DUO senses both that a deceleration is occurring through its own G force sensor AND that the motorhome driver is stepping on the brakes via a connection to the brake lights. Only when both conditions are satisfied will it apply the toad brakes. But since it needs installed you're burning some hours up front but only once.
Most portable ones sit on the floor, need hooked to the brake pedal, and a source of 12 volt electrical power. They push on the driver's seat so they can exert force on the brake pedal. AFAIK they only sense that a deceleration is occurring through a G force sensor. They seem to require ten to fifteen minutes to install or remove and then you have to find a place to stash the unit when not towing.
There's advantages and disadvantages to each, which is why you need to make that decision first.
There's a bazillion posts on this subject over here:
https://www.irv2.com/forums/f85/
Good luck,
Ray