Just got another Korean 100 rd AR drum (Beta-type clone) this weekend at the Columbia show at the Jamil Shrine hall, for $120. I think Centerfire Systems has them on-line for about $145, if any are left. I have a genuine Beta C AR drum, had it for years but have never used it.... it's more of a collectors items now. No need to use it when the Korean ones work so well for 1/2 the cost. Also picked up a Mini-14 drum at Jamil for the same price, but have not used it yet. I have read of others that have had problems with the Korean AR drums, but mine are just fine. I do use a good bit of the powdered graphite that is supplied with the drum, not an excessive amount, but enough to keep it slick. They might all fly apart the next time I use them, but so far I'm pleased with them.