The S33s do have a break in period. They are a heavier/stiffer training tire. All tires loosen up and decrease in rolling resistance with use. As tire casings flex with use, they loosen up and deform more easily. As the tread thins out, the tire deforms more easily as well. The more well used the tire, the lower the rolling resistance (relative to when it was new).
If you find these tires to be decent (as I did), then maybe try the Elite 135. They were my favourite overall tire. I have ridden faster, more supple, but also more expensive tires, but so far, nothing has beat the Elite 135/125 for value as a race tire.