Unless you're looking at owning SSR as a learning curve and selling "up" in 3-5 years, I wouldn't buy at SSR to trade out if you don't like SSR.
Buy where you want to stay - and book in the 11 month window.
DVC booking patterns have changed quite a bit during its first 25 years. As it grows, it'll change even more. The same prime spots at 7 months that you want will be even more in demand as time goes on and more owners pursue them at 7 months. That has been the case (booking at 7 months has become more difficult over time) and that will continue to be the case.
We originally bought at BCV because it's where we want to stay. We added a fixed week Poly because it's where we want to stay. Our other favorite resort, AKV, doesn't currently require a contract to book at 7 months, but if it did, we'd add on there.
The issue isn't how booking patterns are now, but how they'll change over the contract. I just don't think you can predict 7 month booking patterns 10 years from now, let alone 25. Those patterns are certainly different than 10 and 25 yrs ago.
Buy where you want to stay.
We want to stay at BCV and Poly. It doesn't matter much to me how their booking patterns will change at 7 months over time.
DVC is a big investment. We're happy with it because we will get what we want out of it. If I spent this much money and found out the 7 month window wasn't working for me, I'd be more than disappointed. In fact, this is why timeshares in general get a bad rap, they're too expensive not to get what you want.
Get what you want. Buy where you want to stay.