Has anyone used World Mark/Trendwest? My family has 6 big vacations planned for this year and wondering if this is a more economical way to go. I just got back from a 4 day Disneyland trip and we are planning a Hawaii trip for June, Expedia has Hawaii vacations that are 50% off until 3/31 so should I use the money toward a timeshare for all vacations or just book the Hawaii deal? Anybody use these programs with success? Or are they just a scam?