i went last year, it was quite a good park but TBH i did stugle to do it all in a day. I was only there for a day and it would be hard to pick out the best rollercaoster, Top Gun is like a massive version of traumatizer, yet the on ride DVD is well worth it for a suverneer as it contains some quite good park footage as well as a DVD of you on ride. The italin job stunt tracj was also a good ride with lots of good specal effects, erm carn't rely compare it to anething in england.
They also have a free outdoor waterpark and all of the rides in there are excelent, alot bigger than those we get over there so if your there for 2 days i would recomend at least half a day in there (don't forget your suntan!!!) The standing coaster was a bit disapointing (Sorry carn'y rember the name) and i enjoyed every flat ride i went on!!
Erm, i'll try and rember some more mate but stugling a bit at the moment.
Also if you got to niagra falls then theres a park called marine land that i loved and also if you venture a little way into the US from niagra then Six Flags Darren Lake was the best theme park i have ever visited outside europe
hope that was helpfull, sorry i wasen't there long enought for any of the shows if yo have any percific question i'lkl try and answer them