that's an ******* type answer. . . .
back to the OP,
use what ever you can find that will work. If the milk works for 1 cheese it will work for the rest. I prefer Oberwiess (~$6) here in Milwaukee but have heard store brand Roundys (~$3) works as well. Unfortunately I dont know what markets or brands you have in your area.
Best bet is to get a gallon and make a test batch of mozzarella and if it works out fine for that, then use it for cheddar.