I have white KUT Dianas that are 4 years old - excellent quality and no bagging out at all (although I know that Suz and Aida have a bagging out problem on their styles). I bought my regular size. I wish I had sized up though because they look a little too tight to my eye.
(I am however, allergic to things looking too tight going on three years now).
That said, Greg likes them and I wear them rolled at the hems or tucked into tall riding boots.