Not a fan. I think it actually hurts gas mileage. Not a knock on the ACC in the Ram specifically, just ACC in general as a concept. The computer/sensors don't take into account traffic AHEAD of the vehicle you are following, nor does it react to things like brake lights. Just feel I can drive more gently and efficiently myself than the computer. Suppose you are set to cruise at 75 and you are coming up on a vehicle going 65, or better yet a vehicle going 70 that you can see is approaching another vehicle going 60, or a line of vehicles that just lit up their brake lights. I can anticipate this stuff way ahead of when the computer would react to the vehicle ahead, and can just coast up to the vehicle and be at the set distance I like to maintain between vehicles, with no brakes, no sudden deceleration, just a slight easing off the gas 100 yards ahead of time. My 2 cents.