@oldjeep that's utter garbage and most likely something a brand loyal person would say, so touche..
I've owned a bunch of different (older) ski boats, both with 350s and 351s, and currently a GT40 equipped Nautique. I loved my Malibu with the base 310hp carb'd 350 and never any issues with it, great boat and motor.
But my bubble butt nautique with the GT40 is light years a better ski boat. Motor is rock solid and easy to work on. 351W are known as being uber reliable for obvious reasons. Prior to me owning it, this boat was not cared for as I would have liked, basically driven hard and put away wet.
Yet my 17 year old GT40 still turns over 4800rpm as per spec, idles perfect and holds speed damn well. All I've done is replace the fluids. Did plugs, rotor, cap and belts this past year, all were factory original from the previous owner. A ski buddy has a 95 and similar story.
@jjackkrash all of these parts are readily available from either ski boat stores like skidim or nautiqueparts and many can be cross referenced to motorcraft, ford or other aftermarket parts. The only issue I've heard is the computer program is PCM, while the ECM is ford and PCM no longer services them. The file is available and new or remanned ECMs are available to be programmed. Not a common problem, but with older boats, and a marine environment I assume we'll begin seeing more issues.