I havent used it on SPS as ive always just fragged the coral before its too late then dip the sps in 5mL of lugols/gallon tank water and that works well.
As far as the LPS corals go ive had great success(greater than 95%) with using epoxy to stop brown jelly bacterium, necrosis from sting, and necrosis from bleaching. Think of it as snuffing out a fire. I can't remember where i picked this up...either calfo or fenner, one of their books. but in the book they were demonstrating it on wild brain corals with tremendous success. it typically, if done right(you have to cover some of the still living part to ensure that you stop it) stops necrosion overnight and within a week the coral polyps should be extending or feeding again. It does however, as we all know in this hobby, take a great deal of time for the LPS grow over the epoxy.
hope that helps
Sean
BTW, ive found that the best product to dip in is either Kent tech D, or TM pro coral cure( for tissue repair)