[s-cars] Are Rs2"d S4's that faaaast?

[mirko.il at sbcglobal.net]

Hi guys , I've already asked this question on AW but wasn't satisfied with the answers.I'm planning to upgrade my car from a chip to an RS2'd S car but would like to know if there is that much difference between a chip and bigger turbo 280 vs. 370hp
I've never drove RS2'd car so can't tell , perhaps someone could give me a ride ,any RS2'd car in Chicago area?

Thanks.    
                 Miro.