1) OKW has larger rooms
2) All OKW studios have 2 queen beds (which may or may not be a plus for you)
3) OKW has a relatively large full service restaurant, but lacks a food court
4) OKW connects to DtD by boat and bus, there is also a walking trail...it is about a mile.
1)SSR has 12 additional years of contract life
2)SSR studios have Queen bed and full sleeper sofa
3)SSR has an easy DtD location for walking or boat
4)SSR has a nice food court, and has just added a small full service reataurant.
Both resorts are conected to parks by bus transportation, and the ride length is about the same, OKW is a little closer to EPCOT.
Benefits Disney vs. resale...
Through Disney:
1) Points are available almost immediately...no waiting to clear Disney's ROFR.
2) Financing is readily available, if you need it.
3) Immediate access to
DVC discounts/perks
Through resale:
1) TSS had a post stating new financing was available

2) Generally less expensive than purchasing through Disney
3) Easy choice of several "sold out" resorts, whereas with Disney ou may need to waitlist if you don't want SSR.
Resale Negatives:
1)Points become available after contract offer clears ROFR, closing takes place, and Disney enters you in the system...can take quite a lot of time.
2) Disney may exercise their ROFR, meaning you'll need to start the process over.