One of the problem in coral propagation is holding corals in place until they grow and attach on their own to the substrate. Underwater epoxies, rubber bands, super glue gel, toothpicks may work well but we still have to find a secure spot for the frag. Frag-Mag is sufficient to hold most frag on our reefs glass and allow us to maximise every square inch of our tanks without disturbing other reef inhabitants. This is what I have been using for the last year and I love it! It allow me to hold my frags everywhere and to move them easily around the tank for perfect placement.
I have also seen picture from hobilist using Frag-Mag to create aquascaping arrangements where corals grow right on the glass.