Best advice I can give on saving some dollars is to latch on to anyone you know who currently hunts turkeys. If they have a prefered shell, see if you can pinch a couple, or just buy a couple off of them to try out.

The other great way to do this is to get together a group of between 2 and 5 hunters, and everyone buy a box of something different, then split them up between you. You'll end up getting to try as many as 5 or even 10 different loads for the price of only one or two boxes of shells.