Simple runflat question?

[Frim]

I cant find any Mitchelin run flats that fits the different size front and rear, they do a pilot sport 4 for one but not the other.
245/35 20 and 275/30 20, is it ok to mix say the sport 4 on the front and use a pilot sport 5 on the back? I've got P zeros on at the minute and am sick of them disintegrating.

 

[ALFAitalia]

Don't use run flats would be the obvious answer. You will get better ride quality etc as a bonus.

 

[DSM10000]

I cant find any Mitchelin run flats that fits the different size front and rear, they do a pilot sport 4 for one but not the other.
245/35 20 and 275/30 20, is it ok to mix say the sport 4 on the front and use a pilot sport 5 on the back? I've got P zeros on at the minute and am sick of them disintegrating.

The 4 and 5 versions are just iterations of the same tyre so no issues doing as you suggest.

What car is this for?