Every high powered rear wheel drive is a POS on snow, BMW's are no exception to that. I've owned BMW's for more than 15 years, but have moved over to Audi. My last BMW spend 3 months a year in the repair shop, the service was a complete joke. All that electronic gear, they're stuffed with nowadays is problem prone. Mercedes is also having major problems with reliability. In Germany they are not even in the top 5 of the ADAC-listing on that subject. If you the best in performance, give the Audi A8 a test drive. No BMW or Mercedes comes close to it's synthesis of road holding and driving comfort.