We just installed the Brakemaster system for our 2012 Jeep Wrangler. I used it this last weekend for the first time and have to say it works really, really well. I don't have any hard data but it seems as though the time from brake to full stop has increased minimally, if any.
Based on my limited experience (300 miles travelled), I would definitely recommend the Brakemaster setup as the way to go!
2012 Fleetwood Discovery 40G
2012 Jeep Wrangler Unlimited Sahara
2005 Chevy Z71 Suburban