I am guessing that is mostly mis-information being disseminated by those with interests in Auto Ord, Springfield, etc. or maybe even STI and Colt snobs. Gun Broker has these for $370 to $390 with free delivery (with the wood grips and flat back strap). If it was widely known how good they were, that would hurt the expensive guys over inflated prices. Remember when the Norinco 1911s came in, the same mis-information was spread. Later, when the truth was out (but they were no longer imported), they became highly sought after for platforms for match guns...
I just did an article for the SASS Cowboy Chronicle (I am a staff writer there) on this Rock Island 1911 for a Wild Bunch side match gun. It gets my all time "Best Buy for the Buck" award. This is one sweet son of a gun! I have replaced my Glock as my fanny pack road trip weapon with the 1911 Rock Island. Even seeing a 1911A1 in the hand is a great deterrent to two legged goblins and malefactors.
On the other one I handled 4 or 5 years ago, we tried a Colt WW2 slide on it, and an unknown GI barrel. It worked great. We also tried a GI trigger and it worked, too. On this one, the hammer, back strap and grips fit perfect too. Out of the box, the trigger pull is about 3 lbs with no creep. When I put the 1911A1 GI hammer and strut in, it got heavier...maybe 4.5 to 5 lbs, but that is OK for a cocked and locked carry weapon. It doesn't rattle, though, like my GI Ithaca did, so maybe the tolerances are tighter. For a carry gun, the wood grips are actually very dense and very pretty.