debating between the not only the cost but the true advantage to 19'' over 20'' for winter driving.
I could just buy 20'' for my turbo II wheels but im unsure taking them off and on and the seal on the tire for my summer wheels decreases performance etc or if thats just folklore or
if im going to be hugely disappointed cosmetically going to a 19 from a 20?

if the ride and driving through michigan winters is going to be noticably different on cold icy maybe lightly snow roads with 19'' ill do them , i wont be heading out in deep deep snow..

 

The main reason would be your selection of snow tires is vastly better. There aren't a whole lot of choices for 20" snow tires. Second, some people say the more flexible sidewall of the 19" tire gives it better traction on snow/ice, but I'm not sure about that. Much bigger difference with the top-rated 19" tires vs mid-low pack 20" tires.

 

Sadly a smaller wheel works better in every way as mentioned above, the rubber has to be harder the bigger they get, they are wider etc. I have to have 20, because of pccb, but 18inch would be the best choice if you have a real winter. The 20s are surprisingly good, but only because of awd and air suspension.

 

hey jeff welcome to the forums!
i think kip has it perfectly nailed, the bigger you go the worse it will be.
20s do look fantastic though. : ) gregg