i've personally used one. i know it cost $4000. it took 13hrs to build a model that was not very complex and only about 8x8x5. The quality was very poor. i could have pressed down with my palm on the table and turned it into 10x10x3. i can only imagine the cost of a 3d printer that would actually turn out a decent, high tolerance, high density part.
Favorite range gun for the money - CZ 75B or STI Spartan V 9mm
Go-to carry setup - Walther PPS or PPQ in FIST kydex holster 1AK
Favorite semi-auto design - HK P7
"A Sig is like a lightsaber - not as clumsy or random as a Glock."