Focus on getting a good fit. This includes:

1. getting the right size for your body dimensions (sizing does vary from brand to brand and model to model)
2. top tube length is just as important as seat tube length (nominal frame size)
3. look at bikes with different geometries as well; some people prefer the more upright comfort-oriented bikes like the Specialized Roubaix or Trek Pilot. The bikes you mentioned have more aggressive geometries that are less comfortable at slower speeds.

You may notice some differences in handling and acceleration between bikes. A lot of this depends on how well the bike fits you. Bikes with shorter wheelbases will tend to handle more quickly. Bikes with longer wheelbases will tend to be absorb more road shock on long rides over uneven terrain.