I have been riding an aluminum mens' frame road bike for a few years, and am ready to upgrade to my first carbon frame. After visiting local bike shops and test riding what is available this late in the season, I have narrowed my choices down to a 2010 Specialized Ruby Expert, a 2011 Specialized Amira Comp, or a 2010 Giant Defy Advanced 2. I typically ride 30 - 60 miles at a time, and would like to attempt my first century. The Amira felt great on the short test ride, but would the stiffness make it uncomfortable on longer rides? Does anyone have any thoughts about these choices? I have also seen a Look 566 origin whick appeared interesting, but I was not able to test ride this bike.