I had a request to put these on a Chiff post, so here they are!
I made four videos of low D whistles with a conical or tapered bore. I still plan to do a comparative video of all of them together, but I did the Onyx feature yesterday evening, and then spontaneously decided to do a feature for each of them.
Onyx: https://www.youtube.com/watch?v=sSET5MQfenw
Shaw: https://www.youtube.com/watch?v=m8gyk5o7h3k&t=326s
Tony Dixon: https://www.youtube.com/watch?v=QiByycDeFwE
Thanks for the videos! It was interesting to see each one up close. Also, you’ve improved notably as a player since the last time I saw one of your videos (maybe five years ago). Sounds good!
Do you notice something that all four of them have in common with each other, being conical whistles, that makes them different to play than cylindrical whistles? Do they have a collective identity in terms of sound or handling? Or are they as distinct from each other as they are from a Burke or MK (or Reyburn, Goldie, Susato, Bracker, Chieftain, etc.)?
Thanks for doing those!
However I don’t think playing outside in the wind is ideal especially for low whistles.
BTW I used to have two of the Tony Dixon conical-bore Low Ds and both of them had a white plastic ring at the bottom which yours lacks. Do you know why that is?
About wind and Low Ds, years ago I was hired to play at a beach wedding. The Bride wanted a particular tune played on Low Whistle (she had an album she liked of it).
The beach here is always windy, sometimes pretty strong, and I tried to sell her on the uilleann pipes or Scottish pipes. I explained that bagpipes aren’t affected by wind, but with whistles if the wind is strong enough they just won’t make any sound at all.
She insisted on Low Whistle and sure enough I was cutting in and out during her tune.
Nice to see & hear what the Shaw sounds like - I have the Tony Dixon & really like it, it’s a great whistle. 
Yes, there’s a lot of traffic noise outside as well, but outside is where I could be and also play the whistles at this particular moment. The wind actually wasn’t too bad, and only pestered me a bit on the Dixon video.
As for a shared characteristic on all four, maybe. That’s definitely what I expected to find when I started, but at this point, I’m not sure if anything that seems similar is due to the conical bore, or other design similarities. No one, unifying characteristic really jumps out at me. I heard someone say that conical bore whistles had a “hollow” sound, and it MIGHT be true, but it’s such a nebulous idea that it’s not very useful. I think a whistle head design would have to be set, and then everything kept the same except for the body shape, and then play them side by side. Each one of these whistles has its own unique sound.
Thanks for the comment about my playing. It’s not where I want it to be yet, but I’m glad an improvement is noticeable.