Get cpo I cannot stress this enough my friend...
And as an example I got a 2010 328i w/17k miles on it, with premium pkge and automatic but only rwd for 27k. This was one year ago last week. And I have factory warranty and maint until 04/2014 or 50k miles then cpo kicks in to 100k miles or until 04/2016.
I had it in the shop for issues that was 100% covered but would have cost me $2590 with parts and labor.
And with the stock conti pro all seasons I get decent traction in snow.
And with a turbo version, you definitely want some kind of long term warranty which equals cpo.