Of my 3 exhaust systems, I only have one of these. It's on the generator and the most difficult to get to and inspect. I was just wondering to myself just this morning how I'd know if it was going bad. Can they be taken apart and visually inspected? Are there indications in the way the exhaust/water mixture exits the boat? I had questions like that in my head.
Now that I've seen your failure and repair, I'm wondering: If it's leaking on the outside, might there be significant corrosion on the inside, and how would one know?