An excellent test. Thankyou.
I am another one who has lost the pea out of a whistle, many years ago. I'll admit that I don't know the brand and I'm sure it was a fairly cheap one.
I can see some general wisdom in the sentiment against pea whistles: if you lined up a random bunch of scouts, or even hikers, how many would have a cheap pea whistle like mine ?
I suspect there is nothing "wrong" with any quality whistle, but any "cheap" whistle may not perform when its needed most !
PS - I'm not sure about the wisdom some folk have put forward "...just warm it up ". Yes you can do that, but if you are in a "situation", that may not be possible, or not quick enough to be useful, so although you can do it, its not ideal