As I understand it, the CM discount is no longer 25%. It was until last summer, when it dropped to 15%. For the holiday season they bumped it temporarily up to 20% -- but I believe that ended in December. Perhaps they started a new discount for the New Year?
That being said, what pp's have said is sound advice: buying into
DVC in order to stay at non-DVC resorts is not wise, especially if you can stay at those non-DVC resorts with the CM discount.
However, having stayed at every resort on property (except for the Yacht Club), I would encourage you to check out other places. We, too, love the Polynesian -- but we also love Animal Kingdom Villas, and Beach Club Villas, Saratoga Springs (looking forward to a stay in the Treehouse Villas!), and Old Key West -- we love 'em all! We're really looking forward to a stay at the new Bay Lake Tower sometime, as well. Even with the CM discount, staying at the Polynesian can be pretty expensive, and often there are no rooms available at the Cast rate when we try to book. Our typical stay is to use the CM rate for the weekends (avoiding the high points), and booking DVC for the Sunday through Thursday timeframe. With DVC we feel like we have a lot more options.
That being said, if the Polynesian is the only place you ever want to stay, then buying DVC would not make sense, even with a CM discount.
