MakerBot Print is our newest print-prepration software, which supports native CAD files and STL assemblies,
allows you to interact with all your printers via the Cloud, and many other exciting new features.
That's the million dollar question... it depends on how well (smoothly) printed the internal surfaces are and if you have applied a coating of silicone lubricant to the surfaces that move against each other. However, 4 - 5 seconds is about right... but it also depends how hard you can spin it. As explained in the information provided this won't spin the same as with real bearings but that is partly due to weight keeping them spinning .... but this costs far less and is 3D printed.