investing in technologies like "3d printing" or "drones" is dicey as fuck.
you may think you hedged your best on the safest firm that is making the best items in that field. Then all of a sudden the field changes, that small company you invested in sells to a larger one, and you're stuck with minimal or no gains. These are emerging technologies, so they aren't safe bets. its not like GE is making these items, they are getting built by small firms.
GoPro on the other hand successfully branded, they took a simple concept (ultra portable cameras / mounted cameras) and attached their name to it.
wish i would have gotten in on GoPro stock when it was cheap as balls, now it looks like their gaining days are near done. Unless they can find a way to peak again my guess is they are going to stay stagnant.