They say it draws 18a and can be run on a 20a circuit, but they suggest a
30a circuit.

Until I get around to ripping all my cables out of my work shop and redoing
them properly (I have already bought the subpanel...) I only have a 20a
circuit, so I am wondering if it actually works.

And, how do you like it in general? JDS actually said that for one machine
their 2hp would be adequate, but I figure on something like a CMS you need
all the air movement you can get.