It might depend on what you are riding now. My ride is the Cervelo RS and I also have ridden the R3. But the big tryout was the S3 for about 4 days. It was like what the OP had as far as components. Weight wasn't a dramatic difference between the RS and S3, but those tubular Zipps, that fast spin up on acceleration; the S3 on fast descents, unbelievable.