I used to run wire bead Vittoria Randonneurs (700x28) but my rear tire sidewall was starting to bulge so I decided to change both the front and rear tire. I replaced them with kevlar bead (i.e. folding) Specialized All Condition Armadillo Elite (also 700 x 28). The difference is like night and day - the Specialized tires are considerably faster than the Randonneurs were.