Tennessee Tornado has to be one of my biggest surprises. I expected it to show me my spine, but instead it was awesome fun.
I also have to nominate the loop portion of Son Of Beast. After having most of the bones displaced on my body leading up to it, I was shocked when the loop was smooth and fun. Of course, this ended a few seconds later when the ride re-entered bone destruction mode.
Biggest unpleasant surprise is The Voyage, only because of the insane overhype it gets and it's supposed to be the best wooden coaster in the world. It's not. It's not even close to that. My one ride in 2010 was one of the worst coaster rides I've ever had. Rough, painful, nothing positive to it at all. I'm sure I'll hear the usual "but you need to ride it during the full moon during eclipses in odd numbered years" or whatever theories are always tossed about about "when" you should ride a ride, but if a ride only delivers a decent ride during very specific and very small time periods, it's not a great ride.
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