I'd wager you'd find it would be more than it would be to rent from a Worldmark owner by the time you calculate the cost of the maintenance fees from the Wyndham points you'd use, plus the exchange fee. As has been said, it's not clear whether VIP discounts would apply (I would guess not since it's not Wyndham inventory). Some have suggested a ratio of 1:16.4 (a 10,000 Worldmark reservation would cost 164,000 Wyndham points) but I don't know if that's the final word. Ron included some documents that show it in the other direction, it's not too far an extrapolation to think the conversion would be similar going the other way.
If there are Worldmark locations that interest you, you might want to check out a Worldmark ownership. There seem to be a lot of happy Worldmark owners and the MF's are among the lowest of the points systems.
That ration 1:16.4 was info provided by a member of th Worldmark Board of Directors. He is in a position to know. A typical 2 bedroom in one of the older Worldmark resorts is 10000 credits in red season , but the newer resorts are often more. You can see the credits requirements for each resort by going to www.worldmarktheclub.com and clicking on the "resort gallery" link. That will bring up a map. drill down to an individual resort and the seasons and credits requirements are posted there... apply the 1:16.4 ratio and there you are.