I use 35mm Vittoria Voyager Hyper at 50-60psi on my townie/errand running drop bar bike. I run 25mm GP4000s tires on my carbon fiber road bike at 80-90psi. The Voyagers really impress me, they feel like they roll every bit as well as the narrower GP4000s. The ride is so good on the wider Hypers @ lower pressures that it makes me want to go with a 25/28 GP4000S II setup (when it's released) on 23mm wide rims @ 70psi on my Specialized Roubaix.