I got my helix earlier in the week and I've used mine with a katana 100 straight into effects loop and it sounds alright, it's hard to tell at home as I can't really crank the katana. I don't have any PA system at home to try. Will try it straight into pa next practice session and compare between sound from the katana. At the moment my plan is to try a combo of katana and pa. Using the katana as a monitor for myself by going out on one of the loops before an IR. Then the main output goes to pa after an IR block. I will compare the two and come back here with results if I remember. Another option I may potentially explore is 4 cable method and see about using the midi commands from helix instead of the GA-FC (which is what I used along with pedals before the helix).