Originally Posted by DocC3

Consider the Cannondale Slice. I ride a Roubaix compact and a Slice Force. Early this season I bought a 2012 Slice from a guy who hurt his knee and wasn't going to be able to compete this year. The bike came with a Zipp cockpit, but without wheels (installed Reynolds Assaults). I had a professional fit and had no problem getting into a comfortable aero position. I raced the Slice in both sprints and olympics as well as doing a number of training rides. This bike is stable on straights and corners. Over the same 15 mile training loop on back-to-back runs, the Slice is faster. However, I continue to ride my Roubaix for training and for sprints that have more turns or hills. Last year I installed aerobars on the Roubaix. I didn't change the set up because the fitter who installed the bars said my position and saddle angle is what he would recommend for a starting point for me. I recommend you try aerobars on your Roubaix before you buy a TT bike. I believe the experience I had with the aerobars allowed me to work more effectively with my fitter on the Cannondale. I also was able to get comfortable more quickly on the TT bike because of my experience with the aerobars.