I wish I. Old take credit for this, but there's a local shop near me that gets all my business now because of their customer service alone. The owner holds an event every third Thursday where he holds blind taste tests. You get a card to fill out everything about th juice (scale of 1-10, what flavor you taste, and so on). He buys three brands that he doesn't carry, and let's everyone try them out. So, obviously a great way to get feedback, customers, and possible new products, also, if there's an overwhelming majority of people who like the stuff he orders it. It's actually a lot of fun, really puts your senses to the test not knowing anything other than its ejuice.
I even thought about having get togethers just to do this myself.