I had a chance to shoot the SIL's Bushmaster a few weeks ago and even though I don't shoot long guns too often, I was able to kill a couple of clay pigeons at 100 yards with iron sights. Used only five rounds to kill two birds.
Piqued my interest in the platform. I suppose, if I did enough research, I would consider buying but I've got other priorities at the moment. I've always liked the M16 look, full size, irons, nothing fancy..
Let us know what you finish Alf, I'd be interested in whatever you come up with.