My problem w/metal stringers hasn't been the noise, so much.  Rather, I've found I have to use a minimum of two clips on larger fish to ensure they don't twist, pop the single clip, and self-release.  I've lost more than one bigger fish that way.  In other words, I have found big fish to be less secure on metal stringers.  On the other hand, I don't recall ever losing a fish on a nylon thread style OR a nylon line-with-plastic-locking-clips style stringer.

Of course, in the old days I tended to keep bigger fish more often.  That wasn't very smart.  Nowadays, I mostly release the big ones & keep only eaters.  I suppose a metal stringer would work fine now... unless, of course, it's a pollyhumper.  None of the above work very well with them.

Jimbo   8-)