I too have entertained the idea of getting one. I have heard good things overall at ARFcom, and there are some things that can be done to make the work better. I do know that there is a company in Idaho, I believe.. Mad Dog or something like that, making good reliable mags for it, and they are regular AR size magazines.
From what I have read, they seem to be more accurate with the 1/12 twist rate A1 rifles, but work well from the 1/9 as well. It does appear to be barrel dependent though.
-Bidah