The second main reason is the straight back stock of an AR15 doesn't fit me well. I have a long neck and this is a known problem, but there are ways around that. My choices would be a PWS MK116 or a Mini-14 customized by Accuracy Systems. For a level playing field, I would choose the sub 1.5" MOA to get the barrel down to 16.5". I'd choose the .750" barrel. Any opinions on these two choices?