Good post, Dave.
Some other points. While a mechanical system may or may not be as reliable as an electronic system, the mechanical system can be checked for wear----------an electronic system can't.
I started with the Unified/US Gear system. It worked fine for the first year and a half. Then I had 2 black box failures (poor soldering on the circuit board) and than the vacuum pump failed. All happened in the middle of trips. Lots of white knuckle driving pulling a 5000 lb toad without toad brakes!!!!
I replaced it finally with a Ready Brake system. It was easier to install than the Unified system and worked great. I'll never have an electronic system again.
