Figuring out if a flavor needs more shots is one of those "subjective" things. I know, I want raw data most of the time. But with MBV, the option is awesome. With my butterscotch, so many variables come into play. If I'm drinking beer or eating food, its flavor changes. If I vape it too long, it becomes muted. With my chosen flavors (butterscotch and caramel), I decided I preferred extra shots. I do not suggest going over 3 shots of extra flavoring on your first try. I suggest start low and work your way up. With their prices, you're not gonna break the bank.