Anyone with a 40 ss have any of the known issues with the 525 headers on this boat? Seems the boats that are having the issues are high performance offshore applications.

525 CMI headers are a issue on any boat. If you have a leak you end up with water in the engine. Check out stainless marines SS manifolds. No power loss and no tubes

All 525 pipes will leak sooner or later. Salt water is really hard on them and should be flushed with Salt-A-Way after every use. Like Fossil Fuel said, Stainless Marine is a better option.