Just picked up a (new to me) 09 800GS. 30 minutes into the ride home confirmed that once again the boys from Bavaria can't design a good looking comfortable OE seat. After some research I decided to take a chance with the Seat Concepts seat. Slightly wider and firmer foam than the OE seat.
The install was very straight forward. Pull all the staples from the seat pan and remove the original cover. Remove the OE foam. Place the new foam on the seat pan, then place the new cover on the foam. The foam is custom molded to fit on the pan. Then just begin stretching and stapling the new cover in place. The OE seat pan is fairly soft plastic so a good quality T-50 type staple gun will suffice to drive in the staples. I did not need to use my air gun. I am really satisfied with the quality and after a few two hour rides the seat is nice and comfortable.
After that I added the BestRest products light bar on the front. What an ingenious simple design. Just pull the 4 screws that hold the front fender, then put the light bar plate in between the two fender pieces. Total install time - 10 min. Best Rest also had the simple luggage rack for the back on sale for almost half off!!