If you own a timeshare and also become RCI member by paying some extra dollars then you can avail timeshares across the globe.
I had a timeshare till 2009. The advantage was that my family were using two weeks in timeshares in two different places per year till 2009. Yes, RCI membership allows you to do that in addition to discounted car rentals and flight tickers. We haven't been to even a week long vacation since then.
Timeshare made us travel oriented, because we had an investment that we wanted to fully utilize. That investment 'forced' us to plan a trip and go. Now that there is no such compulsion, we have not been travelling at all. People suggested that we were wasting our money in timeshare and that we can plan a travel, go there and enjoy on our own at less cost. Well, from my personal experience, even if we were going, we would be spending more.
However, I would suggest that the timeshare annual rental should be economical and the Management approachable to make it viable..