Earlier post was reported to be expired because coupon code will not work when you apply it when adding item into the cart.
List of state that SuperBiiz charges tax: Arkansas, California, Connecticut, Georgia, Indiana, Iowa, Kansas, Kentucky, Massachusetts, Michigan, Minnesota, Nebraska, Nevada, New Jersey, North Carolina, North Dakota, Ohio, Oklahoma, Pennsylvania, Rhode Island, South Dakota, Tennessee, Utah, Vermont, Washington, West Virginia, Wisconsin, Wyoming. Customers outside of these states will not be charged sales tax.