Fascinating article.

I found it very interesting that the Coghlan's whistle I bought "until I get a better one" turns out to be one of the best performers. Guess I won't be replacing it after all.

(I also have a Storm in my GHB, and the Fox Micro in the AMK PSK in the GHB.)

Also interesting that the metal survival whistle that came with another PSK I was given is the lowest performer of the bunch. Well, I put it on my keychain for more mundane whistling, so that's not a problem.