How do you find the mechanical properties of the parts? Do they vary print to print? Do they suffer from the same problems that cheaper 3D printed parts do - principally either very low strength across the layers (for FDM prints) or very soft materials (cured epoxy and most of the SLS prints I've dealt with).
The pieces were pretty damn durable. (I couldn't break them by hand). They used either Nylon or Glass Fiber reinforced Nylon.
Mechanically it should be very similar to SLS, but uses a deposition style more like SLA. So in theory it should besomewhere in between.
The material I've read and demo material prints I've seen so far back that up. Should be good for small run cosmetic and functional demo prototypes, but you want see it used for mechanical short run production parts.
Can't get into the details on evaluating part quality other than to say that I personally think MJF parts are awesome - completely different thing than FDM. Just considering look and feel, MJF part density and texture create the perception of quality.