rare/classic guns are realy neat to have and even play with, but if you are concidering buying one i would do some research on what you are buying and what would be good to use.
just remember, with rare guns comes rare hard to find parts. if you break something it could cost you out the keester to get replacements if you can get them at all.
i have a few rare/classic guns and exarach has had quite a few and we can both atest to the pita they can be. its great being able to show up at a game with something that no one else has, but when something goes wrong you can be uterly screwed