I think its cool Knight offered them but in all honesty its not hard to have a better rifle built for $2000. GM even sells the .450x.458 1-18 cut rifling barrel blanks if you wanted one as close to a Knight 500 as possible.
About the only thing you cant get is the Boyds stock WITH the bedding block. You can buy the exact same stock from Boyds but im not aware of any place you can buy that bedding block.
Very nice rifle but im a little disappointed they did not retail for closer to $1200 and let you add the additional options you wanted.