Mixing tire brands

[boxstershorts]

Context:
I have Michelin PS2s all around. The fronts are due for a change but the rears still have some life left in them (not for lack of trying).

So I am shopping around and being told to not mix anything with Michelins because the side wall is much stiffer and will cause very noticeable handling effects. That other brands can be mixed but not with Michelins

I'll probably get another 5-8k miles left on the rears and want to get what I can out of them so I would to have to change them out prematurely.

Any experience out there with mixing another brand with the PS2s?