I used to ride in a collegiate for lessons. It was a decent saddle. Reasonably comfy for me and seemed to fit most of the horses. It was older too and still in great condition so I'm guessing they hold up pretty well. I also like that you can get models with the gullet change system which makes it easy to fit a wider variety of horses. Overall I think it's a good pick for a middle of the road saddle.
I don't know anything about the circuit saddles :(