May I add that I drove on track with mixed tyres in the wet.. Now I was always skeptical about how much it affects the car... You would be suprised.
I did a trackday with cragus in the car on mixed tyres and the car was terrible.
Anybody that says mixed tyres dont matter, try a reasonable pace drive on a track in the wet and it will all come to light
Both ends give way at different times, both ends react different when cornering, both ends react different when hitting standing water