Definitley Six Flags Great America. You never hear anything about this park because they dont really have a stellar coaster collection compared to MM and GAdv, but it is by far the best Six Flags park i've been to. All coasters were running with max capacity (Bull and Whizzer even with 3 trains) and none were stacking, thats amazing in itself. Also the rides there are in very good shape, the park and queue lines are well maintained and cleaned, also an amazement in itself. The ride operators are very efficiant in throughput (except Ragin Cajun, but I could see they were having issues getting the ride to dispatch without proper weighting) and amazingly are very upbeat in their job and do a lot of interacting with customers. By far the best selection of flat rides in the SF chain and they are all in very good shape (no ghetto carny flats here). They also play the Demon song in their queue ::COUGH PGA take note COUGH::
GAm's Hurricane Harbor is incredible also, very detailed theming and nice to walk through and a lot of aweosme pro-slides.
The big surprise of the park was definitley Viper though, as we're walking through the queue line it looked exactly like Psyclone and man I was NOT looking forward to that! Then when we got on the ride (like every other coaster at GAm, no stacking like 20 minute wait) and went up the lifthill grabbed on tightly and hoped for the best. We go down the first drop and get some decent air and think "Wait, this cant be right" then do the turnout hill then go over the next hill and get some nice air again, and got confused. Then the next turnaround hill theres a double down and we got EJECTED out of our seat, insane air, then the next hill ejected out of our seat again, insane air, then a turnaround hill, then the next hill ejected out of our seat again with some awesome air then got ejected out of our seat again with insane air. When we went into the block break my friend and I looked at eachothother like "WTF just hapenned!?!?!?" Had to go on it again to verify, but yeah SFGAms Viper definitley kicked ass and is smooth, not bad for a ride that looks exactly like Psyclone.