DVC is a big investment and buying a property that you know is not the one you are hoping for, IMO, could end up being a mistake.
While many have luck at 7 months, you just never know if you are going to get what you want.
We spent an extra $5000 to buy in at BLT because we knew we would not be happy if we were anywhere else, unless it was our choice. While many have had success booking BLT, I just did not want to have to wait and hope until the 7 month mark to know if I was going to be at the resort I wanted.
However, since we plan to visit WDW for many years, even if I consider owning for only ten, I really spent an extra $500 per year to know I would be at BLT--well worth it for us. If I spread that out even longer, since we plan to visit for many more years than that, the cost is even less.
If you buy at another resort with the intention of always staying elsewhere, you could set yourself up for disappointment. BCV is small and getting exactly what you want for all the nights you want might prove tricky.
However, if you really don't care where you stay and if BCV comes through, great, if not, that is no big deal, then buy for cost. Or, if you know you can't book before the 7 month mark anyway, buy for cost.
Other than that, buy a place that you know you will not mind staying if that is all you could get.