Ty,
I use the polycrylic all the time. I've never tried spraying it, but I have tried the rattle cans. Absolute mess!!! Tried all the tricks I know including "hot potting". The spray pattern just splattered the stuff. I almost never got the finish sanded back to smooth. If you try a spray gun, it might take a little tweeking to get everything set just right. I've had good luck using the foam brush method applying very thin coats, usually two, sometimes three.
Paul