I'd go with the Easton's... I have a couple pair of the tubular version on the EA70 and I love the wheels. I've ridden a set of the Ksyrium SL's before, and they just didn't seem to spin up anywhere near as fast. On the EA70's I feel like the bike wants to go as soon as I do, and I just don't get that feeling from the mavics. As always, YMMV.