If I buy, I will use the $5 per point off my downpayment. I don't really see the "free vacation" as free. IMO, it costs the amount that you are losing on your downpayment.
If you purchase 100- 149 points you get 3 nights stay, 150-199 a 5 night and 200 a 7 night stay. Your 3 night stay would cost between $500 and $745 (or $166- $248 per night), your 5 night stay would cost between $750 and $995 (or $150 - $199 per night) and your 7 night stay would cost at least $1000 (or $142 per night). While the $166, $150 and $142 are great prices for resorts like the Poly, it's still not free ... especially when you're paying $7,500, $11,250 & $15,000 respecively for the timeshare!