Thanks for the replies. It's good to hear the performance is not too different between the groups.

I guess I'll have to figure out how important weight is to me. 170 grams between the two groups doesn't sound bad at all. I'd love to add a spidering hollogram crank, but that just throws cost into an entirely different realm. It may seem silly but I'd really like to go a little weight weenie on this bike. I know it's engine first, but i find the "make it as light as possible" aspect fun.

I weigh options heavily and research for months before I finally make a decision and greatly appreciate everyone's input.

I had a campy chorus 10 speed bike and although I liked it, I'm going shimano this time around.