What is the seat tube length of new Madones (54cm) from center of bb to tippy top of seatmast clamp? I'm thinking its 56cm or 57cm but not sure. The bike shops where I Iive don't stock 54cm in their stores. I would imagine that a Pro Fit or a Performance Fit 54cm have the same seat tube length, so owners of either, please chime in. Thanks!