RS just take all the fun away from driving and make it a rather dull experience, even more so if you happen to use a wheel.
It seems all the tires got stickier from the first demo of GT5 I played at GamesCom last year to the retail version, but the RS more or less are now overkill.
Handy for those races I did just for the level ticket without the need to shed loads of money on buying a car or upgrading it, but I don't come to the interweb and brag about my laptimes while failing to mention I used RS and SRF
For those moaning that RS are the way to go online: make some friends, race SH and enjoy how multi-layered the driving experience of GT5 can be.