I have the '07 Synapse feminin carbon 3. I really like it - although I'm not sure how much my opinion counts, since it's only the second carbon frame I've ever ridden. (Like you, my other choice was the Specialized Ruby Comp.)

It does seem like the 105 chainrings are wearing way too fast - not that I've been the smoothest shifter this year, but geez, there's not even 1500 miles on them.

I'm just a B-level club rider and this bike is great for me. The only thing I've changed out was the saddle, and swapping the cranks for a shorter set.