Blue Mountain Ontario Timeshare A Good Idea?`

I've been reading information on buying a timeshare and the adage seems to be to buy one close to home, one that you will use or that will allow you to trade for what you want. These points lead me to think that Blue Mountain Ontario, Whistler, BC or Mont Tremblant, Quebec, would be good choices for us. We are open to other Ontario timeshares as well, if they give good exchange value and are enjoyable to stay in as well. Does anyone own at these resorts? Can you give me some advice? I've been looking for ones at Blue Mountain and they seem very expensive compared to timeshares in other places. Perhaps I am not finding the right ads. Can I only exchange for other Intrawest properties? All 3 of these locations have non Intrawest timeshares but are also Intrawest developments. Out of the 3, I thought that Blue Mountain would be the cheapest to buy at. Any thoughts?

Thanks.