A couple Thomsons, Bontrager Carbon, Easton EA70 and various cheap ones. I don't notice much of a difference but I choose Thomson for my CX bike. I don't want to break a carbon seatpost on a remount.
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I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC