depends on what you want out of a car i guess. R is more racy, S is (yep softer) and more cruisey.
R - recaros, rear wing, lsd, lighter
S - leather seats, sunroof, bigger rims, wider tyres, tad more power.

the S has a bit more power but is also a bit heavier. i think someone said that the suspension geometry in the facelift version is better than the pre-face lift, but don't quote me on that.