Yeah, if you've been to Alton Towers before, go to Thorpe Park, however if you have not been to AT before, then I suggest you do go there. Some people say Alton Towers is overrated as the best park in England, I disagree with those people strongly, because as a day out for enthusiasts and the GP alike, I don't think any of the other English parks compare.
Anyway, am I wrong in saying Port Aventura is a tussauds park? If it is, I'd go there