I am with Lou. now one other brand I will mention
Ready Brute with Ready Brake
If you are towing a car or truck or van you REALLY need an aux braking system.
The Ready Brute with Ready brake (Blue-Ox offeres a competing product by the way) inludes a Surge brake System.
These have both advantages and disadvantages...
We may, from time to time, change the way we load our car or motor home so the brake "Ratios" need to change, Following initial set up Ready Brake is self adjusting
When the car pushes against the motor home (Stopping) the device pulls the brake pedal down (it is a pedal puller) adjusting for things like residual vacuum in the booster, and load in the car, all automatically.. The "new car" kit is not all that expensive when you trade towed's either.
The down-side
The unit uses a cable that is much like the parking brake cable on most cars.. now living as I did for half a century plus in the great salted north.. I am used to those cables rusting, binding and not releasing the parking brake once applied.. Same happens with the Ready Brake cable,, So you need to check for binding every time you hook up and I'd suggest keeping a spare cable handy just in cuss, and/or regular lubrication (Yes you can lube a cable, motor cycle shops have the device you need to do it)