I believe that if you have a place where you want to stay, then buy there. I would not recommend, simply for price, to buy a resort that you would not be okay staying at if you can't trade out to what you want at the 7 month mark.
We bought BLT because we knew that if we were forced to stay elsewhere, we would not be happy. We looked in to SSR as it would have saved us over $5000, but in the end, we just knew it would not make us happy.
We spent the money and own where we love. We have stayed at the BWV, BCV, and VWL, and BLT and BLT remains our favorite.
Now, if you would be okay owning at any resort and if your trades come through, great, if not, that is okay, then absolutely go for price.
There are very few times that you won't be able to find any availability elsewhere, but depending on when you go and what you want, it could be frustrating.
For example, both BWV and BCV are very tough to get in the fall during F & W. IF you don't own there, you will have little luck at 7 months. Nothing is impossible, but some things are less likely than others.
Certain room types are also very difficult unless you own at that resort. BLT SV rooms are in short supply, AKV concierge and value rooms difficult, and BW view and SV rooms at BWV, again, very tough to get.
December is a very popular
DVC time because its lower points so many book their home resorts at 11 months. Trading out during this one can prove difficult.
Good luck!