Old Fashioneds are really easy to just do yourself. You can spend extra on the Proof syrups if you happen to like how they taste but an Old Fashioned is ridiculously simple. It's just three ingredients! Like the line in an old movie said, "What could happen to an Old Fashioned?"

I find they're easier to make with simple syrup than a sugar cube, which is probably the "mix" you're seeing in bars. Using syrup means you don't have to spend time muddling bitters into a sugar cube. You can buy simple syrup or just make a batch, which takes all of seven minutes or so. On the stove put a cup of sugar and a cup of water in a pot and bring to a simmer. Stir so the sugar dissolves. Pour it into a container and store covered in the fridge. It will keep for at least a week or two, probably longer. If your syrup is old just look for stuff growing in it before you use it.

In a rocks glass, pour a shot or two of your whiskey of choice. Add a slug of the simple syrup you made, to taste. Add a few dashes of Angostura bitters or orange bitters. Stir. Add ice. Add an orange slice or a cherry to garnish if you like. Drink.

I usually add about 1-2 teaspoons of syrup and 3 oz whiskey, as I don't like my drink sweet.