I will second 3D3 Solutions. I stumbled into structured light scanning while using David-Scanner, and realized it was the way to go.
Our custom built scanner uses the 3D3 Solutions software, and knocks the pants off just about every commercial scanner out there, in terms of quality, accuracy speed and versatility. Oh, and don't forget cost. Those $50,000 commercial scanners out there have about $1000 worth of parts, and $49,000 worth of marketing.
I just scanned a 1/4" sawtooth and then scanned an entire motorcycle with the same hardware. Good luck pulling that off with another scanner.
As for scanning people, it works fantastic. Set it up right and it captures an entire face (or body) in <1s; laser scanners are simply too slow to make good full body scans. You can scan faces in indoor ambient light, but may want a shade canopy for full larger body captures, depending on the power of the projector (more light/lumens is always better).
-Dan
Global Inspection Solutions
www.globalinspectionsolutions.com