I wonder just how long I'll be able to hold up even though I'm 18-20, because I've been riding coasters since I was tall enough to ride them. My issue is more with equilibrium than getting beat up. I can ride Hulk and Dueling Dragons fine but if I ride anything with inversions twice in a row, I get nauseated, especially in the heat. Rn'RC is actually a coaster I have to brace my self for because I bang my head on those horrible Vekoma restraints, Manta is another one that I am cautious about because the pretzel loop is probably the most intense element on any coaster I've ridden. Both rides I love, I just have to prepare for them more.