evl, This may be from left field on the mix & match tread patterns & brands.
This is jmho
, but I'd think carefully about what you're thinking of doing. The PS2's have a sharper initial bite upon turn in than the G/Yrs. The biggest complaint about the G/Yrs is that they "feel" slow on initial turn-in. I kind of think that the carcass construction is perhaps causing this, the shoulder doesn't roll over quickly so the tire feels slow vs most others. I would expect that the PS2's on the rear could yield a slight bias toward over-steer, where the fronts respond slower than the rears on initial bite. In the dry this would proly be so slight that it could be a non-issue......I'd be a bit more concerned in the wet. The tail may actually slide more than the fronts due to the differing water evacuation methods of each tread pattern.....again, I'm only saying in 'theory' because I've never driven on PS2's. I compare notes with all my C5 & C6 buddies that use the PS2's.
sorry I'm not making too much sense trying to dissuade your mixing brands & tread patterns. It's like this as I see it: both tires are good at what they do, but they get there by different routes....that is due to matching carcass construction to tread pattern to get a result. The issue ( to me ) is will the grip & response be the same from both ends of the car? Specially in the wet.
Tom