Vodka orginally was distilled from grain. Potato vodka came later. Vodka can be made from many things, as long as it is starchy, but grain is generally considered the best and most popular. It's a personal thing, but if you like grain, then look for rye, or wheat. They are the best.
I prefer potato vodkas, and vodkas snobs will tell you they are not the equal to grain based vodkas, but they are wrong. The best tasting vodka out there is potato based. It's Chopin. Many taste tests have been done and this one continually ranks as the best.
But, as I said it is an individual thing.
If you are going to go for the premiums, then don't mix them. Try it right out of the freezer over some fresh ice. Maybe a little tonic, or a squeeze of lemon and/or lime. Enjoy.