ROFR
As Tom so rightly said, you shouldn't care either way.
A couple of the closing companies that are associated with most sales on ebay claim near 100% closing rate on their properties. If that's true (sometimes doubtful, but i'm taking them at their word), that means that Marriott has not exercised ROFR in a long, long time. A recent conversation with an attorney who works for one such company guaranteed me that their recent experience with Marriott was indeed 100% closing on their sales of timeshares, including those sold on ebay.
And if you look at the number of Marriott timeshare properties that are added to ebay each week (average about 4-5 a day), it's a bunch. And they sell for some pretty low prices.
I've been following them for months now, and there are bargains to be had. That is, for those who wish to risk the upcoming "changes" prior to knowing exactly what's coming. Personally I don't think it'll matter much to those who value a cheaper resale in lieu of buying into the points system for a new "vacation experience" at a high price.
Resale ownership will always give you occupying and trading, regardless. That's all most people want anyway. Worth the risk? I think so. You'll sleep in the same beds as the guy who buys into a points system, or who bought from developer. Sorta like the guy who flies on cheaper fares or FF miles. He's always the one smiling.
We bought initially from Developer, but have learned a bit since.