Ditto what's previously said I let tyres run out longer in summer versus winter, but still need to be careful in summer as sparse rain intervals can have greasy roads.
Got nice 1.5-3.5 degree weather there for my Goodyear Ultragrip +'s performed superbly even when giving it a bit of throttle through corners, but nothing I'd regard as extreme for the rubber.
With regard to the PS4S vs PS4, the PS4 is a summer tyre that can be used year round, the PS4S is very much a summer tyre, and does become fairly useless come the winter months in my experience hence I run winters.
The battle between Goodyear Asy 5 and Michelin PS4S, has been raging for a while with very much a draw between the two, it will be interesting how the Michelin PS5 performs.