Ah, the good old radio failure. I had one of those shortly after I got my PPL. Couldn't transmit but I could recieve. Then I had one week this year where it was one thing after another when I was flying with students. First was a flat right main after we taxied off the runway. Next day a door popped open on takeoff and then the next day we had our oil pressure spike about redline and stay there after doing steep spirals, mx said we had a congealed oil cooler. I know those are pretty weak compared to what you guys have experienced but hey that's all I got.