It sounds to me that most power fliers would benefit from a trip to a gliding club and a few high aerotows in something like a K13, which is often used to demonstrate spinning.
Discuss the purpose of your visit with the club CFI beforehand and most would oblige with some spin demonstrations. As previous posters have mentioned, the lack of torque effect from the engine, plus the ability to listen to the air, as opposed to the engine, will make spin demonstrations in a glider all the more useful.