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.
The BNC3D Sigma machines use 3mm filament, with a bowden tube and direct drive! Richrap has a few reviews of the machine. You'll see the stepper motors in there are rather long for high torque. So it certainly is possible. Personally I've been able to do it too, but the motor wasn't the strongest available and only worked well for lower speeds.