Silvaire1, I may take you up on that offer! You don't want a matching AT150 Transponder as well by any chance?
I've got a King Mode C transponder that seems to work fine, but the Narco comm and nav do make me a bit nervous. It does take a certain weight off my mind seeing good ones coming out of service and available. That's why I bought a good spare comm for $250 USD, to have it ready to slide in if needed. I'll think about some kind of upgrade someday, maybe in 2020 when I'll need to do some avionics work anyway to be ADS-B Out compliant.
No problem today regardless having Center hearing & seeing me and calling 737s as my traffic.