Dude it is all about the sugar. I tried vodka, I would always run out. Sugar is easier to measure, and easier to keep on hand IME. Not being a drinker you might not have the same problem.
I did vodka for a bit, it works, IMO sugar is just easier to measure. No syringe, just a spoon. Works just as well.
I did not take the conservative increase method, IME you can go faster if you actually watch your tank.