This is an open question to all: what is so great about the .450 Bushmaster cartridge? It seems to me that ballistically it is the same as a sabot slug for a shotgun, and the shotgun itself is cheaper than an AR. Also, you can get an AR in .308 that has better ballistics, and is cheaper to reload AND buy. To me, it seems if you just want a heavy-grained cartridge for brush work in a semi-auto platform that you should just get a Mossberg 930 in a rifled barrel. I ask this question because I want an AR and I think the concept is cool (and very useful in Middle Tennessee), but it's hard to justify the cost for all that. Any thoughts?