If it is really important to stay at BCV or BWV, then I would buy there. If you are okay staying at SSR or OKW, and will not be disappointed if you can't trade out at the 7 months mark, then buy one of those.
IMO, I would not buy HH or VB to stay at WDW. It prevents you from booking anything until that 7 months mark and you may or may not find what you want, where you want, for all the dates you want. And, while you save upfront, the MF"s will make it more expensive in the long run. Since those are the bulk of the
DVC cost, it needs to be weighed carefully.
I know it seems like 7 months out is a long time, but for DVC, some reservations go right at the 11 month window for owners. For example, early Dec is really popular and most book at their home resorts exactly 11 months out.
As others have said, Oct is busy at both BWV and BCV due to Food & Wine. We bought BLT because we want to stay there, unless it is our own choice to try someplace else. We travel in August, and from everything we read, a lower demand time for DVC. However, we did not want to risk something happening down the line and finding that we can't get what we want.
Saving a few thousand dollars upfront, IF where you stay is important, was not worth it. However, there are plenty of members who own resorts that are not their favorite but are okay staying anywhere. If this is you, buy for the price.
I just read a thread yesterday from a new buyer who can't get in to BWV or BCV around early November and is upset because he was lead to believe that booking during "Choice" season (lower points) meant that getting reservations at the 7 month mark would be easy.
It never is so good luck!