Ray- I know what I have my Heil on not a 756pro II but it does work well with my 746. I get audio reports and when contesting I switch to the narrow setting or use the Proset5-ic. Oh the Heil I use is the HM-i. I dont know about the newest one they came out with. But for the money compared to the Icom desk mics, I have gotten my money's worth. Reid KC5YKX