Snow Tires

Just bought a great 2000 M5. Wow! Unfortunately I have to drive it through a MN winter. Any advice on snow tires? I have an extra set of 18" BMW wheels off of a 7 series. Will these fit the M5? Can I put some low profile (245/40-18) snow tires on these and use them?

I belive all BMW lugs are the same so it should work. Personaly I think snow tires are just one of those things that people think gives them more traction, yet it wont help you one bit if you hit ice. But if you wana spend the money Im not 100% they make low pro snow tires. Ive done some on a M3 before and they were a bit bigger then stock. Im sure if you go to a tire store or your dealer they could give your prices on tires that would fit.