These Michelins replaced the Pirelli P Zero Nero all seasons that originally came on my GTI and they have exceeded all my expectations. I cannot recommend them enough! I was dead set on summer tires at first, but someone told me to check these out and a month of research later I bought the Michelins.
I started autocross this year and I'm topping the GS class after 2 events with these tires against guys with more experience - some with max performance summer tires! They still can't believe a 500 rated tire can be that sticky.
Ride and noise: The Pirellis were pretty good but the A/S3s are noticeably better.
Dry traction: Way, way more grip than the Pirellis. Just as fast on the track as similar cars with 200 treadwear rated tires.
Wet traction: As good as the Pirellis were IN THE DRY.
Cold temps: No noticeable drop-off in grip compared to warmer temps.
Snow and Ice: I'd call them manageable. In light to medium snow, they were fine. On ice, I can't recommend them. I just barely made it up a ramp to an interstate overpass to get home after a couple hours of freezing rain.
Other than snow and ice traction, the only other negative comment I have is I think the sidewall could be a little stiffer. Even with 45 psi, the front tires were wearing past the shoulder indicator on the track.
If snow and ice traction is a priority for you, choose another tire. If you don't see a lot of snow and just want an excellent all-around year-around tire, look no further.