I appreciate the responses (keep 'em coming!). Some feedback:
Unified Tow Brake -- This is what I've been using for 7+years, probably the most sophisticated design and performance, but.. Very expensive to move from Liberty to Wrangler ($1250 labor!) which seems unwise because the device is no longer made. When spare parts run out it's game over, and I already have needed to do emergency field repairs (the control module burned up internally, had to drive the Rockies brakeless).
SMI Stay-In-Play -- Closest in design to the Unified Tow Brake, though SMI's control system is not quite as sophisticated. Is it also vulnerable to component failure? Installation quotes are approx $1000, seems high, don't know if it can be a do-it-myself job.
ReadyBrake/ReadyBrute -- Quite interesting, but every towing/RV shop I've contacted has either refused to install this, or wants huge $$ and won't warranty the work. They say it's horribly difficult to install and seems impossible to have reliable performance...different braking force when turning, or wheel locking, or no braking, etc. Same with the similar BlueOx.
RVibrake2 Auxiliary Braking System and similar devices that get put in-out-in-out-... -- I have no experience with this, but worry about the hassle factor. Even stowing the device while driving could be a pain in a small Jeep. Or am I misunderstanding?
