I have a 2004 Audi A4 1.8T Quattro. I went through 2 sets of OEM Pirelli P-6 tires during the first 60K of this car's life. The Pirelli's are good tires but they don't last too long and they were a bit noisy, so I decided to give something else a try. I had recently purchased some 20 Yokohama Parada Spec-X tires from TireRack for my Mazda CX-9 and LOVED them, so I bought a set of Yokohama Advan S4's.
What a mistake! I've hated these tires from the first day and have regretted the decision every day since! I had such high hopes given the excellent results I had on my Mazda, but it just didn't translate well to the Audi.
The main problem is that on several stretches of interstate highway east of Seattle, these tires cause the car to drift left and right (sometimes violently) as it floats in ruts on the highway. There's a 3-mile stretch of highway on I-90 near my home where I need to move over to the right-hand lane and knock the speed down to about 50 or 55. If I'm in one of the center lanes and am driving with the flow at 70 or 75+ MPH, the car handles like I'm being buffeted by 90 MPH winds! I'm not making this up or exaggerating. It seems that the design of these tires is such that certain highway crown shapes combined with my AWD Audi Quattro lead to frightening drifting and floating within the lane. The fear of being pushed left or right into adjacent lanes has totally taken the fun out of driving. Mind you, this doesn't happen everywhere. And after 35K+ miles on these tires, I know know where all the danger zones are. But I shouldn't have to keep a mental checklist of sections of highway that require special treatment.
No doubt these tires perform well on lots of other cars, but if you have a sporty Audi A4 1.8T Quattro like I do, do yourself a favor and look elsewhere unless you want to drive like Granny Smith in the slow lane. I just ordered a set of Michelin Pilot Exalto A/S and can't wait to put the fun back in my driving!