I recently got a Specialized Tarmac and got a 49/XS.
I am 5'4", 125 lbs, and I have a 29-30 inch inseam. I have a longer torso, with average arms.
We had to shorten the bracket that holds on the handlebars (name?), and that was it. Otherwise, it fit.
I can't imagine riding a larger size.
"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather, to skid in broadside thoroughly used-up, totally worn out, and loudly proclaiming: WOW WHAT A RIDE!!!!"