So I'd like to get me a super high capacity mag for my AR. I imagine that the Beta C is the best, but I'd really rather not shell out $270 for one. That also rules out the 150 round one for $400. So I'm looking at the SGM and KCI knock offs of the Beta C, or the MWG single drum 90 rounder. They each go for $120-$140. Has anyone used any of those? I can find very few reviews for the SGM or the KCI, and I see some for the MWG, but it hangs down lower, and it seems like the offset drum would cause the whole rifle to sit awkwardly. Looks like the MWG and KCI are both capable of being stored loaded, which is a requirement for me. I also like the clear backs on the Beta C and MWG. Beta C sells the clear back separately, so I was wondering if that would fit the KCI or SGM. http://www.atlanticfirearms.com/storeproduct896.aspx http://whatacountry.com/ar15-100rd-dual-drum-magazine-kci---cal-5-56-223.aspx http://www.mwgco.com/ar-15_accessories/product/SBI-90PD-CC.html Any opinions or facts for me?