Originally Posted by
Creakyknees
aren't 303s basically the same weight / profile as the AC420's?
fwiw, I've raced on (older) 404's and (newer) AC420's and by subjective "feel" the 420's felt faster.
zipp 303s are: 45mm rim depth--------total weight 1171grams
american classics 420 aeros are: 34mm rim depth-------- total weight 1530 rim depth
pretty significant difference i would think.