I think you can't go wrong with a Thomson post. I don't think it will feel "harsher" in a carbon frame. That said, I have an FSA K-Force carbon seatpost on my roadbike:

http://store.nexternal.com/shared/St...rce=googlebase

I bought it largely because it is available with a lot of setback, but I was also looking for a two bolt design, and this one is infinitely adjustable and just as easy to adjust as the Thomson post on my cx bike.

Not crazy light though. I think it's probably heavier than the masterpiece.