4 stroke valve adj--truth or myth?

I've got a 2003 Yahama 60 hp 4 stroke with 300+ hrs on it. I've asked the question of several "Yahama reps" at boat shows, "do I need to adjust the valves on this engine ?"
Nearly all say that this is not usually an issue with this engine.

No doubt this has been a great engine, but I am not totally convinced.
Any actual experience from boaters out there???

Thanks

[TimS]

What does your owner's manual say? My F200 calls for valve adjustment at 500 hours, if I remember right.

Tim

[boats.net]

Valve clearance inspection or adjustment is every 400 hours or 2 years on carb models and every 500 hours or 2.5 years on EFI models.