Don fvcking Juan

I had my two front tires replaced about 5K miles ago but now the rears need replacement as well. Rather than just replacing the rears with the stock Pirellis, I'm planning on getting a whole set of the Dunlop Winter Sport M3s and trying to sell my two farily new front tires.

How much should I look to get for them? I paid $250 a piece and they've got about 5K on them. Do you think I'd be able to trade them for the cost of mounting and balancing the tires at an STS or wherever else I go?

Suggestions, or offers for the spare rubber, are welcome.