I voted for "other" just because I have stayed at the AKL concierge and loved it! I have no experience with the others. If you have an opportunity to stay at any location of concierge I don't think you could go wrong.
Voted for BC concierge but the only concierge we've ever done is YC, whcih was AWESOME! BC service, overall, is second to none so if we were to try a concierge again it would definitely be there.
We have stayed at the GF, WL, BC, YC, AKL, & Poly Concierge (Before renovation) locations and enjoyed them all for various reasons. Previous posters make great points....
If I had to narrow it down to 3 and then 2 and then 1....it would be...
BC, AKL, Poly
then....
BC, POLY
then....
BC! Great Location, wonderful service, SAB, etc....
Perhaps you can choose the Resort that most appeals to you and stay there...or if you have a longer trip...maybe try two resorts!