I typically wear a size larger but had to return it for an extra large. The extra large fit well except in the torso length but it is tolerable for me. The padding is not bulky but still comfortable on long rides (40 miles).
Smaller than normal for Castelli. After having several Castelli bibs I figured I knew my size. But these seem a bit tighter than other XLs. I have a 34 waist, 510 tall. Also the suspenders are shorter than my other velocissimo bibs. Comfortable on long rides, a good purchase.