There is a similar thread on the M5 site. There are alot of considerations and risks if you do not go OEM. I find the OEM route a bit salty for my taste(I know, then what am I doing with an M6...). I just called Tire Rack and they still have not gotten a hold of an M6 to set up. I am in a quandry between seriously buying an older (semi beat up)Ford F150 4X4 or the tire set up.
My winters here in south central Pennsyltucky (my apologies to KY) are unpredictable. I do have a 4Runner for my girlfriend but for some reason she does not like the idea of me using it as a backup vehicle (maybe some issues there).
I am very curious to see what you all come up with options. According to the Farmer's Almanac (which has been shown to be a better predictor than the the NWS) this winter is going to be a bad one for this area.