AWD car with winter tires... Doubt you'll notice any snow performance issues between the two...

You may notice better dry road performance with the 17" set-up, though... plus, the car will look better..

I've run the 17" set-up on three different RWD E46s.... and, they are all tanks with winter tires.. nothing can stop them... Take the best deal and run with it..

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2006 330Ci ZHP Imola Red
2011 X3 Bluewater
1987 325iS Bronzit (retired)
2011 Z4 Space Gray (retired)
2008 X3 Sapphire Black (retired)
2005 330Cic Silver-Gray (retired)
2003 325i Sport Steel Blue (retired)
1967 2000CS Delphin Gray (retired)