PS2s got my vote, but I'm moving on the the SuperSports once my PS2s are cooked. Since you don't track your car and deal with rain and winter, a new option might be Michelin's all season tire A/S3.
I just got back from a tire testing session with Michelin US at New Orleans MotorPark for their release of the new Pilot Sport A/S3 -- all season tire.
Michelin was pretty ballsy. We did several wet and dry tests, where the new A/S3 easily outperformed the competitors top all season tires. But the ballsy move by Michelin was with the dry autocross:
I got to drive identical STI's with A/S3 against the competitors SUMMER tires on the dry Autocross. Long story short, contrary to expectations, I turned faster laps with the A/S3's over the Conti DW, Pirelli PZero, Goodyear F1, and Pole Positions.
Hands down, the dry Autocross was the most fun -- the instructors wanted us to drive some laps beyond the limit to get a feel of how quickly all the tires broke away and recovered. The A/S3's were so predictable compared to the other summer tires -- all this from an "all season" tire. If I wasn't driving, I would have never believed it!
Oh yeah...The other drivers in my group included a couple of the guys from the ALMS series: Johnannes Van Overbeek, Tommy Milner, and Patrick Long. Watching those professionals do their hot laps in the STi was nuts.
BMWCCA article from the event:
Michelin Launches Pilot Sport A/S 3 in New Orleans | BMW Car Club News | bmwcca.org BMW Car Club of America
These tires are due to be launched to the public this summer. I just bought new Conti DWS for my A3 Quattro last month, but I'm ditching the DWS's for the A/S3s once they are released.
Our STi's for the dry autocross. There is nothing like dumping the clutch in a test vehicle!
And the track: