I finally decided to spend the exorbitant $800 to put a Corbin seat on my bike. I've owned two other Corbin seats for other bikes and have been pleased with them in the past. I had some slight fitment problems with those seats, but Corbin made them right in the end. The seat for the K1200S fit just fine right off the bat, which was reassuring for me. I bought the basic front rider, back passenger, and back rest model. No heat and didn't want the smuggler option. Did a 400 mile day on it over the weekend, and it was very comfortable for me. Did that ride solo, but did take some short local rides with a pillion on board, and she liked the passenger seat. For the K1200S, with the acceleration it has in first and second gear, the raised back portion for the rider is greatly appreciated! I feel much more secure with that backstop when the throttle is cracked wide open in the lower gears. Much better than trying to hang on with just the hands. I usually just shift my weight in turns enough to put one cheek off the seat, and the sharper edge of the Corbin, although different than the stock seat, didn't make it any more difficult once I got used to it.
I did like the new position of the passenger, being up and back compared to the stock seat. She felt the same way, and didn't have to worry about sliding into me as much during normal riding. The only change was under hard braking, where the reach to the tank for her was further to brace herself. She liked the feel and position of the back rest, which was very comfortable for her. The seat as well gave more area for support, and she felt it would be better on a long ride.
I'm happy with the look, the feel, and the performance of the seat, and except for the ridiculous dollar amount, very pleased with it.