Not a bad article. I think they left out the most important cost, though it is implied:
The tremendous chilling effect on the exercise of an expicitly Constitutionaly protected right.
Every year, over a hundred thousand citizens are denied their rights by the current “background check” system. It denies Constitutional rights every bit as much as literacy checks on voting or poll taxes, probably much more.
We know that over 150 thousand people are denied the right to buy a firearm each year. Most of those are false positives, which is why out of 73 thousand denials in 2010 by the Federal government, there were only 44 prosections. There has not been a study on how many, exactly, of the 150,000+ background checks are false positive, but all the anecdotal evidence that I have gathered indicates that the vast majority of them are.
--with an inaccuracy record such as that the whole thing is suspect--even more so than the federal terror suspect list , on which the redoubtable Senator Kennedy found himself---