I have the Jacobs, installed by the dealer prior to taking delivery. It is warranted 3/36 and accordingly doesn't afford the opportunity of voiding the warranty because it is there. I don't know what improvements I would make to it. I had a different brand on my 95PS/Auto, and this works considerably better, but there are so many differences between the trucks that a comparison is unfair. The idea of leaving it on when using the cruise (the prior one would disengage) is nice for when you are going up and down small inclines, as it engages on the downhill side, holding you closer to the set speed. . Running empty, it is handy, particularly on off ramps and rolling up to a stoplight, but the "I wouldn't be without one" aspect is when you have a trailer on. When you get to that stop sign at the bottom of the mountain, you have cold truck brakes - PLUS cold trailer brakes - PLUS the braking of the exhaust brake..... Best accessory on the truck...