I have a triathlon bike (Trek Speed Concept) and a road bike with aero bars (Specialized Allez Sprint). The triathlon bike has a geometry that is meant to put your body in the most aerodynamic position possible while still pedaling efficiently and being able to run afterwards. I simply cannot get my road bike into the same comfortable position in aero as compared to my tribike. If you want to prioritize triathlon, get the triathlon bike, and then a good fit. You won’t regret it.