Gentleman ....
It all be a different story if you are going to the race track and want to beat the other guy on the track. Right ... right. There you do want to have the same brand and size of tires on all four corners.
Now take our car, we all know that the rear tires wear earlier then the front tires do. It stands to reason since our car is Rear Wheel Drive. So, all depending how you drive your rear tires do need changing more often. My BMW Service Manager told me once "I see you drive your M3 like it should be driven" I said yes and why not I love it. He replied "Well you do need new rear tires"

Well as we all know the M3 never saw a RFT.
Now we also know (most of us anyway) that we cannot stand the RFT right ... right, so what better way then what the original poster planned to do, is get 2 regular tires for the rear. Why should he get 4 when his front's are still fine? I say go for it there is nothing at all wrong with this as long as I said before you don't go to the track and expect your car to win. For street driving you be perfectly fine up to the time when you see the fronts need changing.
Now I say this since I've driven for quite a while and in the
60's, 70's, and 80's it was perfectly fine to drive in the winter with snow tires in the rear and summer tires in the front. So I ask you what is so different from then to what
ryukin is planning to do? Absolutely nothing at all so
ryukin go ahead, just drive normal till you can outfit the fronts with the same brand of tire.
Also
ryukin bookmark this thread, it is a good one let others know how you make out once spring rolls around.
Happy Holidays !
