Actually, Cedar Point has done an excellent job making the rides smoother this season (even Raptor is smoother). You shouldn't have any problem with Corkscrew. However, even the smoothest wooden coaster can be a bit rough. Although greatly improved, Mean Streak and Blue Streak are still a bit jarring around the curves.
Another thing you can try is sitting in the center of a roller coaster car and near the front of the train on rides like Magnum, Mine Ride, and Blue Streak. These rides have three rows of seats per CAR. You may want to try this because the ride here is naturally smoother. Your not directly above any wheels.
One last comment. Wildcat has two points were sudden stops are involved. One is at the beginning of the ride before the lift hill and the second is at the end. If your prepared for that you should be fine.
I'll let someone else who has ridden Demon Drop this season comment on that one.
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2001 park line up:
Cedar Point: May 5-6, June 11th
(other parks N/A as of 05/02/01