Comparing organic growth rates is one of the most effective ways to compare 3-D printing investments. Taking it a step further, if you compare a company's organic growth rate against the industry growth rate, it can allow an investor to quickly gauge if a company is gaining or losing market share.

Fool.com contributor Steve Heller compares the organic growth rates of 3D Systems (NYSE:DDD), Stratasys (NASDAQ:SSYS), and ExOne (NASDAQ:XONE), and by this measure determines that 3D Systems remains the best all-around 3-D printing investment. Check out the video below to get the full story.

Fool contributor Steve Heller owns shares of 3D Systems and ExOne. The Motley Fool recommends 3D Systems, ExOne, and Stratasys. The Motley Fool owns shares of 3D Systems, ExOne, and Stratasys and has the following options: short January 2014 $36 calls on 3D Systems and short January 2014 $20 puts on 3D Systems. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.