We've been using a ReadyBrute Elite tow bar with an integrated ReadyBrake system for about 10 years so far, and have been very happy with it. The ReadyBrake system is available as a stand alone unit that works with any tow bar, and is simple mechanical system with few failure points and no electronics. Since it's a surge system, it only applies the amount of braking needed to unload the weight of the toad from the RV when stopping.
www.readybrake.com
Dutch
2001 GBM Landau 34' Class A
F53 chassis, Triton V10, TST TPMS
Bigfoot Automatic Leveling System
2011 Toyota RAV4 4WD/Remco pump
ReadyBrute Elite tow bar/Blue Ox baseplate