I tried it once at the urging of my employer, who had a bunch of it in stock, and wanted to use it up. It was sort of a miserable experience; I can't recall what the project was, but it was some kind of frames where I would have preferred M&T joints. Shortly after this, said employer bought a small hollow chisel mortiser for me, so I must have complained loud and long. OTOH, I bought a cheap Kreg jig, and used it successfully on another couple of rushed jobs, and was quite happy with the Kreg system.
Casey