Though President Barack Obama says 3D printing will "revolutionize" the way we do things, some have reservations. Printing in 3D not only takes time, but it can cost a small fortune, says Carl Bass, president and chief executive of Autodesk. He says the industry needs better business models and more breakthroughs before explosive growth can take off. He's not the only one with concerns. "I worry that because of the excess hype, [3D] printing will soon suffer the same backlash as solar energy and electric cars," writes Vivek Wadhwa.