I get this question a fair amount, and it's if beard vitamins actually work. There's been a few vitamins built specifically for beards and some of them are making claims at extraordinary growth. Well, unless your nutrition is utter crap, the beard vitamin won't be a miracle cure. Beard Vitamins are supplements, which means they will help fill in the gaps where you have weaknesses and they are designed for those gaps where hair is made.
Essentially, if you have a perfect diet; then a beard vitamin won't do much. If you have a less than ideal diet, then you can see some value in beard vitamins. Really a beard vitamin is a multi-vitamin that gives you specific formulation for optimal beard growth. It offers a convenient way to take those vitamins, but keep in mind you can get them from your own sources if you need to. I take biotin and fish oil as a mainstay, and sometimes I'll take a multi-vitamin.
So it comes down to your own habits on how affect a beard vitamin will be and if you want to pay for the convenience of a multivitamin designed specifically for beards or if you want to build your own vitamin combination.
Also, save your money and avoid beard czar at all costs.