Everybody knows that the Michelin Pilot Sport PS2 tires that are standard on a P85+ are not long-lasting tires (especially if you have alignment issues). So, when the time comes to get a new set of rubber, what are people going with? There aren't many choices for the P85+, especially in the rear. If you're going with a different tire, please say which and why you went with it.
I would not run different tires front vs. rear. The front and rear ends will have different handling characteristics, braking characteristics, warm up at different rates, etc...
Michelin pilot super sport is not available for P85+ rear sizing. I wouldn't mix and match different tires front and rear, might be dangerous.
Only problem with that is Michelin does not sell PS2's for the P85+ in Canada (specifically, the 265/35R21 rears). Apparently it is a US-specific size. I've inquired as to why this is but have yet to receive a reply from Michelin. UPDATE: Michelin now lists the 265/35R21 size for the PS2's on their Canadian website. I'd personally take credit for them adding it :wink: but it's more likely in response to Tesla using the tire as OEM equipment.
PS2s and Super Sports are similar enough that running them together does not pose a serious problem to a competent driver (lots of my friends have done with success). However, I would only mix the two when the Super Sports could be in the rear.