I've got a cross bike that I ride a lot in the mountains in Santa Barbara both trails and distressed roads. I'm looking to upgrade to a carbon frame. My current bike, is a cannondale caad 8. I has a carbon fork, Maddox rims and tektro cantilever brakes. It's is SCARY coming down hills on this thing. Wheel starts to wobble brakes begin to chatter the whole thing feels like its gonna fall apart on me. I wanted to upgrade to a ridley xfire disc, but when I ordered the frame, the cantilever model got shipped to me. Now im learning Xfire discs are unavailable until 2014 model releases, or at least that's what I've heard from dealers and distributors. I want a setup that feels rock solid dropping 3,500 feet at 40-50mph. Will mechanical discs (bb7, Hayes cx5, shimano c75) be superior to a high end set of cantilevers (FSA Slk, ciamillo or similar)? I like the geometry of the ridley frame a lot and its feather light. Just curious if I should hold out for discs, or build the cantilever frame that got shipped to me.