I found my Seat Concepts seat for the GS to be a bit of a nut cruncher. Fit of the cover and the density of the foam were great. Shape, not so much. Wide in the thigh area when your feet are reaching for the ground, which is where you really don't need foam. The bun area is a bit high so you tend to roll forward, hence the nut crusher.
I did like it better than the stock GSA foam it replaced, but ended up back with the sargent. I may try to trim the SC foam some time though. It is very nice foam. Denser than the GS foam, but not quite as firm as the Sargent.
2009 BMW R1200GS Adventure