anyone done a comparo on these 2 ..
which do you think is better in a country like Australia, where snow is few and far in between

 

The Michelin PS2 is a summer tire rated at Max Performance (the highest level of traction before you get to R Compound tires). Even in that category it is one of the best performers. A comparable Pirelli tire is the Pirelli P Zero System (assimetrico or direzionale).

The P Zero Nero is an Ultra High Performance (1 below max performance) 4 season tire. As such it's wet traction would be better, but it's traction in dry would be inferior to the Mich. PS2's.

Really would depend on your driving style. If you go to the track, or autocross you are probably better off with the PS2's. If you don't do anything above aggressive street driving you may not even notice the difference.

 

You can look at the test results at tirerack.com and compare the two tires. Both tests include the Goodyear Eagle RS-A, so you can use that to show that the baseline performance on the different days was similar.

PS2 on Tirerack
PZero Nero M+S Tirerack Test

 

I have the PZero Nero M&S tires on the car right now. I will be going back to the Bridgestones in a week or two. I like the RE40's better for ultimate performance. They seem to grip better in warm weather and slide more predictably at the limit. The sidewalls are also stiffer, which limits body roll more. The Pirellis will be more of a 5 month tire for me.
I would go with the Michellin's. In Sydney, you rarely get below 0 C.