I'm a big fan of wooden whistles. That said, I've never kept one. I can't say whether I would have kept this one if it was mine (rather than a 3-week tour) but I think the odds are better. Why? It feels less fragile. The wood feels dense and sturdy. And, as I said, it has a "play me every day and put me in your pocket" kind of feel to me. I can't say precicely why. Maybe the walls of the whistle are ever-so-slightly thicker than the Thin Weasel. Who knows...it's just my impression anyway.
Volume: This whistle plays medium-loud. I think it's louder than my Copeland. I don't think it's as loud as the Alba SE. The second octave bit louder than the first, but not extremely so. I don't think this would be as much of a "blend in with the crowd" whistle, unless it was a larger session.
Responsiveness: This whistle is decently responsive. It doesn't feel as crisp and nimble as a Burke Al-Pro. But it doesn't make me feel fat-fingered either. I didn't have any problem playing rolls and crans and the like.
Tuning: Here's where I'd have my biggest complaint. The whistle is in tune, but only with the slide pushed all the way in and by pushing the notes a little bit. This means you can flatten the whistle up, but can't really sharpen it. Other than that, the whistle seems in tune across both octaves. Maybe the air's hotter in Australia, so the whistle's just a bit sharper over here, but it's definitely a problem for me. If I were to get one (which I'm seriously considering) it'd need to have a bit sharper baseline. Since the whistle is well in tune with itself otherwise, I wouldn't expect that to be a problem for Earle.
Other than that, the whistle's breath requirements are consistent across the two-octave range to keep it in tune...no breath acrobatics required (i.e. breathing extra-hard on some notes, and extra soft on others).
C-natural: OXXOOO produces an in-tune C-natural with the expected breath requirements.
Hole size and placement: This whistle has holes are medium-sized. As noted, they aren't all perfectly round, but it's only a minor deviation. I wouldn't expect most people to have problems with hole size or placement.
Air volume requirements: Average. I didn't note that this whistle took any special amount of air to keep playing. I didn't run out of breath especially soon, nor was I able to play for especially long periods between breaths. It's a solid average in this regard.
Air pressure requirements: Medium. The whistle has a small amount of back pressure, and if you're in any way shy, you'll drop from the 2nd ocatve into the first. This is in line with what I expect from a somewhat-loud wooden whistle.
Clogging: This is the first wooden whistle I've ever played that didn't clog all up on me. But then again, I've moved 400 miles away from the coastline, so I can't say that had nothing to do with it. Regardless of the reason, I didn't experience any clogging issues with the whistle. Hooray!
Misc Notes: The tuning slide looks like those on the Thin Weasel or Busman whistles: A brass fitting that slides into the whistle. The "female" joint is also brass, so it's a brass-on-brass slide as best as I could see. I think the female side has cork or something on the Weasel. I don't know about the Busman. In any case, the slide action on this whistle is smooth and easy, but stays put once you get it where you like it. I like it better than either the Busman or Weasel tuning slides, which I found myself pushing closed when playing fast.