Volume: Slightly louder than average. It's a smidge louder than a Sweetone.
Responsiveness: This whistle is pretty responsive. When it's cold, the 1st octave D can take a split-second to come into focus when tongued, but otherwise, no issues.
Tuning: This whistle is in tune, when blown with the proper breath control. Surprisingly, this whistle benefits from being warmed up. I say surprisingly, because most plastic whistles I own don't really have that much change with temperature. But this one really doesn't come into tune until warmed up. When warmed up, there are no breath surprises, though there is a slight jump in breath pressure required between G and A. Nothing major, though. My only issue is 2nd octave D. To get it to play in tune, you have to blow it pretty low, close to the octave break. At my expected breathing spot, it's about 22 cents sharp.
C-natural: OXXOOO produces a C-natural that can be blown true. OXXOXX brings the breath requirements more to center, allowing you to sharpen or flatten the note a little more cleanly.
Hole size and placement: As I mentioned above, the holes are pretty round, and pretty well placed. I didn't even notice the F# hole being a wee bit off. There aren't really any size issues, or placement issues..the holes are nicely spaced apart without being too close ore too far.
Air volume requirements: Below average. I can just play and play on this whistle on one lungful.
Air pressure requirements: Slightly below average. This whistle takes a little less push than your average cheapie like a Feadog or Sweetone. This is a little different than #401, which took so little pressure, it was almost like wishing a breath through the whistle, rather than actually blowing. The cracks might've had something to do with that, though.
Clogging: Like the Whitecap, this whistle had light clogging, but any clogging affected the whistle catastrophically. It didn't take much to cut the whistle out completely. I treated the windway with some Duponol and haven't had any issues since.
Wind Resistance: This was the most surprising category. While the whistle didn't stand up to the strongest Dallas winds, I was able to play this whistle outside with a steady stiff breeze, without any issues. I was pumping gas one day, and had it with me, and the breeze was strong enough I was certain I wouldn't get a sound out of the whistle at all. But it played just fine, both octaves. I love it when a whistle totally surprises me like that.