I have just replaced my seat and pillion with the Suzuki gel seat.
I have both and a grasshopper driver backrest that I can't use with the new seat. PM me if you feel the need.
I have an '07 C-50 and really like it. I am considering moving up to the C-90 for more power. I have yet to ride the '90 but when I sit on them at the dealer the seat seems to be wider than the '50. the sales guy i asked 'did not know' and did not seem to want to go and find out (go figure) from someone else, so I am coming to you folks who may have ridden both....is the seat wider? it does not seem as comfortable to me..i am in the category of 'no-assed' males so a wider seat does matter to me! thnx in advance