Remember that the entire 'pre-ban' concept was an artificially created market. Almost overnight, $700 rifles became $2500 rifles based solely on legislation. There is some controversy as to whether that legislation will go away or at least be heavily modified here in the near future, and what effect that will have on 'pre-ban' values.
One group believes that values will remain high, since any new production will be different from the old - in other words, they are thinking that Colt will not return to selling pre-ban configuration rifles to the general public. This group still advocates pre-ban firearms as a good investment.
The other side of the coin is the group that points out that the functionality of the firearm is really the same, and that if the legislation is removed then the market practically disappears, leaving people holding a very expensive bag.
I do not wholly subscribe to either group. Certain specific models of 'pre-ban' firearm WILL undoubtedly retain its value. Older Colt rifles such as the SP-1 and Gov't Carbine with AR15 markings will never be made again and high-condition pieces will always have a collector following. I believe the later pre-ban Colt rifles will be hard hit if the AWB goes away, because Colt still makes those configurations for law-enforcement sales and you'd better believe they would open that market to the general public if the legislation permits.
AK's will be hit even harder, depending on any modifications to the import ban.
Firearms as investments is a very tricky field. You have to be exceptionally careful as to which specific models will hold their value - not all do.
The autonomic nervous system provides for involuntary muscle function - the work of breathing, digestion, and so forth. On some folks, that's a pure waste of ingenuity.