I don't know much about Marriott's model, but I actually had to walk away from a Wyndham Timeshare opportunity recently. We couldn't do it, because the Wyndham restrictions were terrible. It was a fixed week at a less popular destination, and off time of year. To convert it to flexible points, and to get enough to use at a more desired time/location, Wyndham would have required us to buy "Founder" points (I think they were called Founder, or something similar), and the price was astronomical compared to what we saw as equivalent with what we have at
DVC.
It made me greatly appreciate the DVC model, by comparison.