I am just wondering whether those lovely 17 inch Alpina mag alloys I spent so much money on would fit on the new 120d? The tyre sizes are 225/45-17 and 245/40-17. Might look cool, but can't find any pics online. Would I need spacers? I know I have to work out offset and rolling radius - but not sure how to. If it can be done would it improve handling, or send it bad...? Any thoughts gratefully appreciated. P.