My first "tour" with Wyndham was in Durango. This was before they had a timeshare in Durango (the deed was going to be in Pagosa Springs but they "promised" ARP privileges in Durango once the resort was finished). The Durango resort that was presented never materialized. The current resort is a converted hotel. The rooms are very small. However the location is great.
You would definitely want to see Mesa Verde while in Durango, taking the train to Silverton is fun too although there could be snow by September.
Pagosa is a huge resort with things to do onsite. You can visit the hot springs in town, and if you didn't get enough of the ruins at Mesa Verde, you can visit Chimney Rock National Monument. (I am fascinated by all those archeological sites).
If you're ever there during ski season, you have to go to Wolf Creek ski resort. My kids (now adults) learned to ski and snowboard there. Durango also has a ski resort nearby (Durango Mountain Resort - formerly called Purgatory).
Linda