Is it a good idea using a chassis knockout punch (e.g. Greenlee) on 1/16" epoxy glass PCB material? My concerns are splintering of the glass, dulling of the cutting edges of the punch, and the having the removed piece hang up inside the die. Maybe I should stay with a spade drill bit... they're a lot less expensive to replace.
And can this material be cut with a circular bench saw or a band saw?
It dulls a bandsaw blade. It will break under a knockout punch, fracturing where the teeth bite in. Hole saws are pretty cheap and will do the job, at slow speeds. Wear a face mask!