I recently purchased a vintage Guerciotti, campagnolo super record everything, modolo brakes, s. marco saddle, everything original. i was curious cause now im starting to have second thoughts on my purchase, my question is if i was to sell this and purchase a more modern bike, $700-$800 limit new or used, would i notice a considerably large difference in my performance or would it by minimal and not worth the trade? It seems that after 20miles it gets uncomfortable, but it could just be me. This is my only bike, and i try to ride as much as possible, advice? thx P.S.<Edited by moderators>