Just received my Dixon High D with the Brass Tuning Slide this morning…all I can say is NEAT!! This is my second whistle, and I hope to be adding more Dixons to my collection. It’s such a full, round tone, not breathy at all, and is so easy to play in all octaves. It’s quite a contrast to my Clarke SweeTone Celtic. Plus it’s easier to hold since it’s cylindrical rather than conical. Another thing that is quite nice is that it doesn’t require as much air to jump up to the 2nd octave as my Clarke…therefore I can practice a bit quieter. I hate apartment complexes 
Anyway, this is turning out to be such a fun hobby, and I wanted to thank everyone here for all the support and information I’ve gleaned from you, especially Dale and his wonderful site. Oh, and go support his charity! waves I’m off to practice
Jim