This thing is VERY heavy duty. Your domestic sewing machines are like plastic toys compared to this. The body is heavy cast iron machined out like an engine block to hold the various shafts and cams. Parts turn smoothly. The mechanicals look similar to a Juki 8700. The integrated servo motor is what really makes this machine refined enough for us casual sewers, or even beginners, to enjoy. No big motors under the table to deal with. Most of us don't want a machine that only runs at warp 9 speed. Here you can set the top RPM from 200 to 3700 rpm and you get smooth variable speed (with good torque) up to that top RPM setting via the foot pedal. Having that low end torque makes almost everything easier to sew. As for cons, the instructions are slim, it's not easily moved, there is a learning curve, and you may need to tweak a few things. The Juki 8700 manual is a helpful reference. I use it for fabric and it will go through thick denim/duck hems like butter. A very nice machine.