For whatever it's worth, the Corbin seat doubled my range before monkey-butt set in.
There are several downsides, such as, it's heavier than stock. It took about 3000 miles to totally break in; about 3 times longer than previous Corbins. It is wider, so if you like to hang off, it restricts that maneuver. Fore and aft movement is not affected after the first 1000 miles or so. Initially, the seat rises a bit in the front middle. This softens fairly quickly.
The stock seat is not bad for an OEM, but it is very flat and suffers from foam that is much too soft. I can still do 200-250 on it before feeling pain.
I have done several trips of 450+ miles in a day on the Corbin after breakin without even noticing that I was sitting on a motorcycle seat. That's the highest praise I can give.
When I first got the Busa, I suffered from the numbness in the wrists and hands.I had to stop and get off the bike once, at about 200 miles. I had solved that problem on other bikes by raising the bars. For a bike with sport touring pretensions, the Busa's stock bars are ridiculously low.
I put Heli bars on, and that helped. I added GenMar risers under the Helis and that helped a lot more.
I don't even notice any problem now until about 350 miles. It is still easily bearable at 450+.
[This message has been edited by SlowHand (edited 08 July 2000).]