In the following video, Motley Fool industrials analyst Blake Bos talks about some of his takeaways for 3-D printing investors from the annual CES trade show. He discusses how 3D Systems (DDD 0.61%) has updated its popular Cube printer, and how two companies are currently vying for the low-end personal 3-D printer space, 3D Systems with its CUBEX, and Makerbot with its Replicator 2X. He gives us a comparison between the two systems and tells us his pick of the two. Finally, we hear what the big things to watch for 3-D printing investors will be from here on out.