I was just generalizing, not pointing the finger Having owned an R33 GTST and an R33 GTR V-Spec, both modified, I can definitely say that S-Chassis make a lot more sense as a dedicated track car, where as the R-Chassis are a lot nicer on as a street car.
Not saying either can't do the other job, just saying that from personal experience, I think they are both slightly better suited to one than the other - you can of course spend money and it becomes a moot point