3-D printing is finally getting some mainstream attention, and 3D Systems (NYSE: DDD) and its loyal investors couldn't be happier. The hot stock's more than doubled in the first half of 2012, making it one of the best performers in an up and down year. But after such a big gain, is 3D Systems still a buy? I'd like to offer you three simple reasons why it remains a good pick for growth investors today, which may either solidify your convictions or change your mind.

1: Emerging technology market leader
3-D printing is still very much an emerging industry. Last year, 3D Systems and chief rival Stratasys (Nasdaq: SSYS) combined to generate about a third of $1.3 billion in total estimated industry revenues. 3D Systems was the undisputed revenue leader, though Stratasys' merger with Objet may alter that balance of power somewhat. Still, there are powerful lessons from history on how valuable an early hardware market leader can be over the long run.

Many people didn't even use a computer until after Apple (Nasdaq: AAPL) released its iconic 1984 ad. By 1992, the company had 14% of the U.S. home computer market and had risen over 300% from the day of the ad's release.

Dell (Nasdaq: DELL), which wasn't even founded until the end of 1984 and didn't go public until 1988, had only a 2% share of the market that year but had already grown 450% in its first four years on the public markets. Its latest figure (for 2011) was just under 12% -- but 300 million more PCs were sold last year than were sold in 1992. That could explain why Dell's been a 114-bagger since its IPO.

3D Systems recently offered an interesting chart from Wohlers Associates during an investor presentation, which claims the 3-D printing market will grow from its current market size to over $5 billion in annual industry revenues by 2020. That's some pretty solid growth ahead.

2: Consumer-market focus
It makes little sense to talk about consumer electronics like PCs when discussing a technology few have ever seen in person, doesn't it? Not quite -- 3D Systems is making a serious push toward the consumer market. It unveiled an inexpensive (by 3-D printing standards) desktop model, dubbed the Cube, at the Consumer Electronics show at the start of this year. That reveal caught a number of people, including myself, by surprise, and it's likely a major reason why 3D Systems' stock has so far outpaced its rival's. Stratasys, in contrast, has nothing anywhere near Cube's $1,299 price point.

Once a company gets a foothold in people's homes, it can stick around for a long time. Hewlett-Packard (NYSE: HPQ), which offered the first consumer printer for under $1,000 in 1988, still holds about 40% of the worldwide printer market. But 3D Systems isn't just content to find a place in your home...

3: Strategic diversity
3D Systems' investor presentation, offered last month, has a number of enlightening tidbits on the company's diverse product lines and aggressive market strategies:

  • 7 different print engines using over 100 different materials.
  • Global user base of numerous high-profile companies.
  • Prices range from $1,300 to nearly $1 million per printer.
  • Services revenue doubled from 2010 to 2011.
  • Serves automotive and aerospace prototyping.
  • Produces hearing, orthopedic, and dental materials for medical clients.
  • New products generated $23.9 million revenue in first quarter 2012.
  • Helps museums preserve and display delicate specimens.
  • Introduced 14 new products over the past 12 months.

The company's also made serious consolidative moves, scooping up several smaller 3-D printing companies as well as some other complementary businesses. While Stratasys has focused its efforts on the Objet merger, 3D Systems has made three acquisitions since April, and also completed a major acquisition in January. A recent $100 million offering of new shares seems to indicate that 3D Systems is reloading its buyout gun for another pass, so more additions are quite likely before year-end.

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