Most people don't realize that the objects printed are a little rough and not all that strong. Kinda like cheap plastic solders you can get in the 99c store. It's awesome for prototyping but, the parts made are't for real use. I use a MB to prototype 1/10th size things at my University. It's great. I hate the fact politicians are making them seem like they can print guns. They really can't. Or at least most printers use plastic that will blow up. It just shows how stupid politicians are and how they shouldn't be allowed to make laws. I heard one of the gun grabbers saying how it's so scary criminals can just print a gun now. WTF? I'm sorry but criminals are not smart enough and its way easier to buy a Saturday night special. If they want to ban and regulate 3D printers because of "guns" I dare them to hold one and fire it.
I don't think they would go as far as seize - track/monitor sales and ownership (YES). I am of the belief - if most of govt. could apply common sense and 'see' the opportunity space for technology / and 'long game' benefit - jobs - innovation ... we would not be in anywhere near the mess we are into today.