Pretty much, they get to a certain point and you never know when to expect a failure....

Some people I know (very low numbers) have had them since the late 90's without any problems and others I know went thru sets like they were going out of style.

I have installed a few sets of the Sport tubes on customers boats in the last few years and even bought 2 sets for my new motors ( not yet installed in boat). Now I am having second thoughts and I am considering going with Stellings and Ebaying the CMI's.

I've had the same set of CMI E-Tops since 2001, fresh water only, no issues.

Not sure if it helps but I do drain them if the boat is going to sit for any length of time and drain while trailering.

Brian -

You will not have issues on the sport tubes. The 525 was an inferior product and they had issues.

Keep the CMI's there is no comparision.

Pantera,
These are the Mercury version of the Sport tubes not the CMI's does that make a difference.

from what i have heard some of the triple eng. setups were not supported properly causing problems on the 525's. My cmi's on my 500efi's are 2000 models, Leon did a repower on it a few years ago and i have not had any problems, i pull both sets over the winter and pressure test with air, so far no leaks, pulling them off in a week to check before season starts, i hope my luck holds

what about 575s?

what kind of headers and what kind of problems?

I wonder if the grade of Stainless Steel CMI is using is not as good of a grade that the others are using,being there corroding/rusting causing leaking???

That would explain why the salt water boats are failing more than fresh water

I think my Dad can answer that. He has been through the 525 headers and the CMI E-top and I think has suggested to CMI on the correct material to use, but I will double check. His shop in an aerospace one so they know what to use that will make it last.

not sure on the grade but I seen some stainless rust, Maybe the higher grade stainless might not hold up to heat or get brittle and crack?