If you're serious about milling your own grain, get a grain mill. Especially if you're doing full mashes. Grinder type mills kill your husk and you get stuck sparges. Mine cost me about 200$, but I made my own hopper and upgraded to the stainless steel rollers.
96$ if you don't want stainless and can make your own hopper.
If you're too cheap the corona is ok, but for less than twice the price you get a much more superior product. I've heard good things about the barley crusher too.