I thought I would jump in on this as I have the 05 Dolce Comp. I am 5'2 and I ride a 51cm. As mentioned, the best way to know your size is by riding it and see what feel best for you. I feel computers are ok to give the lbs an idea of which size might be ok, you pretty much have to know what feels best. If the top tube and height feel comforable, then then minor adjustments with seat, maybe stem will make the fit more perfect for you.

I had also tried the Allez Comp in a 50, which fit ok, but I felt it was just too much bike for me as the reach was a little more than the Dolce.

Try and test is best.

~ JoAnn