I have the Garmin Yaw Damper. I agree with the previous comments about the cost of the installation kit seeming to be over-priced especially in comparison to the other two installation kits. Of course, there are other costs that Garmin has to recoop beyond the obvious ones in making the brackets and a couple of cables. $1500 was tough to accept, but I am now glad I did it. It would be a PITA to add it later. Probably not that difficult, but you may want to take Yoga class first. Anyway, after about 30 hours of flying with it, I am convinced it was the right decision. I expect rear seat passengers will appreciate it, expecially in rough air.