When I was studying, I went to two schools, one using semester system and one using quarter system.

With the semester system I had plenty of time to read the material and really explore the mathematics behind what I was learning. With the quarter system I was so busy running around and catching up in different classes that I never really had the time available to sit down and do that. It sucked. I think the quarter system kind of 'beat' the interest out of me because now it is hard to get back into that state of mind.

semester > quarter :(