She's unexcelled at putting her assets to maximum effect, which has resulted in some stunning images. I think that her photographer, who is first rate, also deserves much of the credit.
Even though size is very important to me, I actually find Sable sexier than Chelsea. Sable's leaner, better toned body and softer, more symmetrical looking breasts actually overcome any advantages that Chelsea might have in size, youth, or beauty.