I have not taken the tour yet but knew that I only wanted to own at BLT. We have been visiting WDW since 1994 and never became members before now because we loved the Contemporary and didn't want to stay elsewhere.
So, since I knew I wanted the resort, regardless, I wasn't concerned about seeing the models in person (seeing them on the website was enough for me).
I know there are many members on the boards who have bought sight, unseen. But I am very happy and excited about my purchase.
I do know that the studios at BLT are a bit smaller than studios at the other resorts and that the bathroom sink is in the kitchenette (that some members don't like). So, if you are concerned about this at all, you may want to wait.
However, I think the incentives, especially the price per point discounts are very good right now. If you were thinking of September, it is only a few months away. If it were me, and I knew I wanted BLT, then I would go for it!!
And, if you have a Disney Visa, you can get 6 months, 0% interest on the charges that you put on the card. I was told that it would be for the down payment or up to $2500, but I am actually getting it on the full amount I charged.
Good luck!!