There are only 7 or 9 GVs at BWV, so not likely to get one if it isn't your home resort. At OKW, we have 27 GVs, and they sometimes are available at the 7 month window, depending on the season. SSR jas 30 some, and I would think they would have the most availability. OKW GVs are the lowest point cost. Oh, and AKV will have plenty of GVs too, but I can't remember the number if I ever even heard it!
Oh, and we have stayed in OKW GVs several times. LOVE the space and layout of everything except the kitchen. I actually prefer the 1-2 bedroom kitchens at OKW over the GV kitchens because of the awkward placement of the sink. I've never stayed in a BWV GV, but we did tour one of the single floor ones, and it was spectacular looking.