Like someone else said, if you put Toy Story and Buzz Lightyear side-by-side and there was no line for either attraction, I'd have to pick Toy Story.
But that's not reality and to me, my experience with each ride is a bigger factor. I can ride Buzz Lightyear multiple times in a day, while Toy Story is a one-shot only ride, one in which you usually have to be there for rope drop and run directly to the attraction.
If somehow they can figure out a way to make Toy Story easier to ride 2-3 times a day, it would win hands down. But until then, I'll take my 4-5 turns on Buzz Lightyear over my one turn on Toy Story.