Also, keep in mind that part of the difference is in that the front OEM S02's are slight narrower in tread width than normal S02's. In addition, the tread pattern seems to have more voids than a regular S02.

I was thinking of using the OEM fronts for another car but decided against it for this reason.

So, if you use any other tire, you may just have too much grip on the front in addition to too little grip on the rears.