Pros: Been there done that
Cons: Nice to do once
Garmisch is a beautiful town. It's close to all the great southern Germany sites, which look amazing in winter time, like Neuschwanstein and Linderhof (and are usually closed, so you just get to see them from the outside). The Zugspitze is the highest peak in German, and has amazing views when you're up their skiing, often looking down over the clouds. But the skiing isn't that exciting. I'd get board of skiing there for more than 1 day. Good for a day trip, great views, but don't spend more time than that there.