Winter tire SLK 171 or prefer a simple winter car ??

Hello friends, the next winter is at the door and so slowly I have to think about the “winter shoes” of our SLK ́s. How do you see the thing: Alu ́s with winter tires for tens of thousands or better a small winter car for small money?? Had so far only front-wheelers and with them it went through the winter great. Note: live in the top north of Westphalia, where snowfall will soon be in the lexicon. ( last year you just 5 white days)