The FARO arm is a bit flimsy, Romers are a bit better built. However, if you're only laser-scanning, the FARO may be OK for your application.
If at all possible, get Polyworks, it's pretty decent software.
For a 6" x 6" x 6" part, preparing a complete dimensional report within the arm's abilities might take an hour of total work. If, however, you want to use this for reverse engineering, that's where these devices excel. Creating a complete STL model of unknown item takes 5 minutes or less, once you're familiar with equipment.