I have Gatorskins on my fixed and GP4000S on my road bike. I can't tell TOO much of a difference in ride feel (I'm pretty dense), but I will say that I haven't had any flats with my Gatorskins, whereas I've had three flats in a month on the GP4000S. Chalk it up to bad luck, bad tubes, or something else, but I like the Gatorskins for what I use them for, they weigh almost the same as the GP4000S (folding version), and they ride nice.