I would say one of the “big 3” Marriott, Hilton, Wyndham.
Marriott - Overall quality of resorts and service best of the 3, but also the most expensive (get what you pay for). Has some complexities regarding old weeks system vs. new points system. I personally am a fan of the points system due to more flexibility and availability. Many on here will have different opinions as to why weeks are better.
Hilton- most of the original HGVC resorts are nice and higher quality, some real good values in purchases and maintenance fees, some complexities with new Max program and resorts.
Wyndham- Quality of resorts mixed. The newer bigger ones are really nice, however have lots of older / smaller properties that are not as nice. However the amount of locations and ease of use make up for lack of quality. Also Wyndham tends to have more availability last minute than the others.
So in conclusion if you want the best resorts, with lots of flexibility and locations and you mind paying for it buy Marriott points. Next best Hilton, but Wyndham points are one of the best values with some of the most locations.
Or be like myself and some other tuggers and get all 3
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