Except Knoebel's Looper doesn't have OTSRs and doesn't hurt. It's pretty scary for me. My first (and so far only) ride on it, I was too scared to let it flip. It's intimidating when you're on it. It's fun even if you don't flip, though. Going to let it flip - a least that's the plan - the next time I go to Knoebels. Hopefully next year.