If the bet is with the guy that has to ride one of these, then you're toast. In fact, why would you even make that bet?
However, if someone else was insane enough to make the bet with you, here's how I'd sell Magnum (forgive me Dan).
You've already been on higher rides (Space Spiral, Power Tower).
You've been on rougher coasters (Mean Streak).
You've been on the same type track (Gemini - what does he know??)
You've been through tunnels (Antique Cars - I'm stretching as I work my way down the list).
Your drive to the Point on the highway may have been as fast as Magnum.
Finally, you could do what I did with my daughter to get her onto Magnum when she was eight years old. "Lexi, Daddy would never take you on anything that would ever hurt you". (OK, so that probably carried more clout coming from a dad than it would for you.)
Good luck either way.
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Duane Cahill
Hey guys, I'm back!