I've narrowed my search for a new road bike down to the Synapse Alloy 1 and the CAAD9 Optimo 2. The CAAD has better wheels and components and the Synapse is supposed to have a smoother ride. Initially the fit of the CAAD 54cm seems a bit better than the 53cm Synapse but I'm sure they can fine tune either one. Anyway, i'm leaning towards the CAAD9 but am worried that the ride will be too harsh on long rides. Will the CAAD9 be that much rougher than the Synapse?

Haven't tried the Synapse, but I have done 100K rides on my CAAD9, with no problems whatsoever.

ditto on the caad9, i have the optimo 1 and love it. I have done many long rides on it and never had a problem. Fit is the key. Keep in mind the only other road bike i have had was an aluminum cannondale 2.8. So i have never been on a road ride with any of the new bikes and their fancy materials.

My view is that if you're going to buy a Cannondale aluminum bike, go CAAD9 all the way. If you're interested in plush and comfort on long rides, then spend a little more and buy the Synapse all-carbon model. But between the aluminum Synapse and the aluminum CAAD9, I think CAAD9 would be the consensus. A buddy of mine has been on the CAAD9 on long rides for over a month now and loves the ride quality.

I ride a CAAD 9 2007 model (training bike) - its way lighter and considering they use this material in the system six bikes and six 13 - it aint bad.

Besides - the geometry is already comfotable on a CAAD