I went in April - simply one of the best theme parks I've been to. The whole park was built in something like 6 months back in 2002, but it all looks as good as new, and although the coasters don't have many gimmicks, they are fantastic!
Superman is one of the best B&Ms I've been on with a huge amount of air time. The woodie there is really fun, and long too. Batman was ace, and they even theme their queue lines for rides such as a topspin; the way it should be done. There is a strange little madhouse there too which is good. Stunt Fall was fenomenal imo, was just so thrilling - wanted to ride and ride again and again. A Vekoma probably beating a lot of coasters I've ridden. Definitely worth a visit if you're planning a trip to Europe!