I put these tires on my 330ci ZHP (sport pkg) to replace the Bridgestone RE040's that came on it. The difference was striking. The RE040's were rock-hard with a tendency to tramline and wander. Anyone who has this car knows how responsive the steering is (could also be related to the staggered setup). Living in the Seattle area I wanted something that could get me through all seasons yet still be a performance tire. The Pilot Sport A/S looked like they would fit the bill.
The tires are very quiet (I could actually hear the engine and exhaust over the road noise!) and they ride smooth. Of course, the smooth ride comes at the expense of a bit of cornering. I believe the sidewalls are a bit softer than I'd like for way I drive, and the turn-in could be a bit quicker, but it's trade-off I've made for now. Driving through a dumping rain storm in the Siskiyou range last year with water sheeting down the road surface, I never felt any indication of hydroplaning. These tires do a good job of cutting through standing water. I can't speak to snow/ice traction because the car stays in the garage on snow days.
After 17000 miles they are still pretty quiet though not as quiet as when new. The treadwear is good with 6/32 and 8/32 remaining on rear and front, respectively. I'm not sure if I will buy these tires again because I'd like a slightly stiffer sidewall. I just put Conti Extreme Contact DWS on my wife's 2010 A4, and so far those seem to grip the road like crazy. I'll see how those last and may try them next if I decide to go with all-season's again.