Since the purpose of winter tires is to facilitate winter driving and 17" wheels are better suited than 18", I went with a set of near-new (i.e. gently used) 17" wheels (acquired from a member here at E60) and added Blizzak LM-25V tires.

While the handling is not like the 19" setup, it?s still quite good and the 17" size provides for an additional cushion against pothole damage.

 

I agree with Jonathan that 17" is the best bet for winter.

(I think I also smell a new signature coming from him too...either that or his RF account was closed!)

 

I just ordered 18 inch no name wheels with Dunlop Sport 3D's for my winter setup from Tire Rack. All in, they were about $1600. I'll let you all know how they perform in the Colorado snow on my 550.

 

18" ASA JH3 with Dunlop Wintersport M3s. A little noisier than the LM-25s. Very capable in the snow.

 

There you go :


Nokian Hakkapeliitta 5 225/50 R17.
I like 17" better in snow. Wintry roads can get very bumpy (at least here) so I prefer
a bit softer combination in wheels & tires.

 

I would love to be able to put winter tires on the stock 172's as I plan a set of 20's for the nice weather. That would be ideal for me but try finding a dedicated snow tire to fit the 172's. It just doesnt exist.