I'd honestly say that ACC is probably the best option I have on my car. On really congested roads with people constantly trying to cut in I might prefer to drive the car myself, but on a long run all I have to do is steer. The system make a 6 hour drive infinately safer and the car almost drives itself. It's a little quirky until you get used to it, but I thoroughly recommend it.
535d MSport Carbon Black / Black Nappa / Fineline Anthracite | Visability Pack | HUD | ACC | Adaptive Drive | Folding Seats | 4 Zone Climate | Surround View | Pro NAV | USB Audio | Professional Audio | Sun Roof | Comfort Seats | Heated Seats Front / Rear | Professional Rear Seat Entertainment.