Officially, ti is supposed to be 60% of the weight of steel, and 6 times as strong, but has a nice springly-like flex property like steel, with high fatigue resistance. That should make it a much better material for trials than any of these materials, however because it would be made with such thin walls, it would dent easily. So if they were made with thicker walls, although they would be harder to dent, they would be hugely unneccesarily strong and expesive, seeing as the material is expensive and much harder to make frames out of.