I haven't used VAULT. But, I have used SAN's original product V-12. It tastes great; but, you need to use a lot of water, as it's very sweet. It works pretty good and I used it for about a month, when trying to drop weight. It worked good for me.
Because of VAULT and V-12 Turbo, regular V-12 has been marked down BIG TIME. If money is an issue, you might want to go that route. GNC or Vitamin Shoppe is a great place to look for V-12 on sale.