I first bought the Eb. While I wasn’t bowled over by it, comments from others inspired me to buy the tubes for D and C Orioles. (The head is interchangable between keys).
My main problem with the Eb is the insane amount of air needed to bring the top two notes (of the second octave) into tune. While the top two of the D are still loud, it’s much less than the Eb. And the C is perfect. This is definitely going to be my “go to” C whistle for future performances.
Everyone is different, but I had to tape the top hole (nearest my nose) quite a bit in order to flatten the C and C# notes, so they were closer to being in tune. Same thing on the key of C whistle, but the notes affected are different, of course (B and Bb I think).
These whistles are nice looking, the tone is good (not buzzy or recorder-ish), the price is right, they are loud and very wind-resistant. Good for outdoors, although the C would be ok in coffee shops and the like. If you can’t afford a high end loud whistle, and the regular cheap whistles are not loud enough, Oriole is the choice.
If you are beginner and you don’t like these, put them aside for a while. You’ll probably like them better as time goes on.
And don’t forget those ear plugs!
Tom.