I upgraded mine to Zipp 101 (which I found on sale at a local bike shop), and I paired them with Conti GP 4000s... and I am in love with them. What a difference -- the Zipp have a wider rim and stainless steel spokes. They really made me faster and, in part, it is because the ride feels smoother. I am one of those people that, while I love the idea of custom, I would not know what to ask for.