I own both an RCI timeshare and three Disney Vacation Club properties. The RCI one is pretty terrible and hard to book unless you book far out in advance. Most people I have spoke with about RCI all say the same thing, that its just about impossible to book something in a short term window unless its a low demand property.

Disney is a completely different story and I am grateful that I bought into disney 13 years ago. DVC points can be used to book not only disney properties worldwide but also disney cruise line, adventures by disney and a large collection of RCI and big name hotels worldwide. Generally though the points used for anything but Disney properties in Florida or California are not cost effective as it is also very easy to rent disney points for between $10-13 a point.

If you are interested in renting I recommend immersing yourself in the disboard dot com forum, specifically the rent/trade section of the board.