I'm planning on dropping to a 90mm/6* stem to tweak my fit a little. since I'm in for a stem anyway, is there a reason I should consider a carbon stem over an AL one?? any tangible benefits to ride quality or stiffness?? seems to me, outside of the very high end pieces, there is virtually zero weight advantage even over the stock Cannondale C2 I already have, might even just look for a 90mm version of that on the 'bay.

thoughts??