I ride older more durably made steel framed bicycles. I do this for two reasons. Firstly lower model frames from the steel era were made of heavier gauge materials and were thusly imbued by their cheapness with durability from some manufacturers. Secondly down model steel bikes were made of 1010 steel which is looked down on as cheap. The truth is the best riding bicycles I have ridden were all 1010 steel frames. 1010 steel is unalloyed, unhardened steel which means it is maleable and supple. This really reduces road vibration but raises the weight of the bicycle. For Tclong03 a lighter bicycle for competition is more suitable for your task at hand. There is no reliable evidence available on the internet to help you determine which frame/fork material to trust. Steel has the advantage of being a real world durable material with a long well understood history of how to make bicycles for specific purposes. The other materials appear usable but there are caveats to all materials and I advise doing a lot of research including the thoughts from this Forum thread.