I've been looking for a slightly used Specialized Comp. The 06s have 9 speeds in back and two up front. The 07s have 10 and 3. The 08s have 10 and 2. Is there a consensus on 9 vs. 10 and on 3 vs. 2? To the extent I can find the year I want, I'm not sure whether I prefer an 06 or an 07. Used 08s will be out of my budget until well after I pull the trigger on one of these bad boys (or something else).