Cameron G.wrote a review of Castelli Leggerezza Bib Tights on June 28, 2010
I am rather skinny and first bought a Medium, one size up from my US size. They were massive despite the other review and the recommendation in the sizing chart. I exchanged for a Small my normal size, these are still not tight. It's not worth the money to ship back again to the states from Australia though so I might have to put up with them plus there is no XS.