The new 2005 Gun Annual (Harris publication) at newsstands now has a good comparo article on DPMS, CZ, Kuehl .22 guns/uppers and a Ciener conversion. Author's best 50 yard groups with the DPMS were similar to my own. He got right around an inch at 50 with the Ciener in a 1:9 barrel, which I found a bit hard to believe based on my own testing with a conversion unit in a 1:9, but then again last weekend I shot some groups @ 25 with a conversion unit in a 1:12 barrel that I wouldn't have believed either unless I'd shot them myself, so who knows? Maybe his 1:9 barrel liked .22s better than mine does. The Kuehl produced the two smallest group averages at about a half-inch (@50) but also shot some surprisingly BIG groups with a couple kinds of ammo. The CZ shot quite well, too.
Interesting article and prolly worth the exhorbitant cost ($10) of the whole magazine if you're looking at .22 ARs and trying to make up your mind. Oh, no mention of the Bushmaster, of course--too new.