Colossus is a coaster when i'm at Thorpe, I'm not borthed if I don't ride it or not. Personally I hate the vibrations during the ride, find the last 5 heartline rolls boring, and the hate the Assault course I have getting in/out of the train due mine height and the Bulkiness of the Restraints. It may of put Thorpe Park on the Map for Coasters, but it doesn't ride like it used to be back in 2002.
The trains haven't been replace stance it been open in 2002 (apart from the otsrs in its 1st season), I think it to do with the certain type of wheels it uses in varied weather conditions