My advice would be to lose the "all or nothing" attitude, and work to get THIS rifle reclassified. Remember, the government doesn't know a Bushmaster from an AR180B....and there is all the supporting documentation you could want showing this is a hunting rifle. It will be a WAAAAAY easier sell then going for all the AR's at the same time.
Now, once this one is reclassified, THEN go after the others

You will have precident that no one has gone postal since reclassification...even the ones that were painted black!
You can then file on the basis that the Armalite, etc. are exactly the same gun, with the same (now established) purpose.
Work smarter people, Remington has given us a huge "in" with this rifle...don't waste it by trying to bite off too much at one time