Giddings Kadja vs Greg Black 4GSD for euphonium

[Tallarry]

Hello!
I have to choose from some mouthpieces for euphonium:
Giddings Kadja
Greg Black 4GSD
I'm also thinking about the Hammond 11ML...
I usually play solos, so I need endurance and high range, but in rest, I need a darker sound to mix with the rest of the band...
What should I choose? (only from these models if possible)
Thanks!

[JasonDonnelly]

That's a rather interesting bunch of mouthpieces you've got listed there.

Do have (or have access to) any or all of these mouthpieces? If so, then test each of them on both your solo music and in a band rehearsal, if possible.

If you don't have access...then it's sort of a shot in the dark...especially considering how expensive G&W and Greg Black pieces can run (upwards of 165 USD).

Are these the only mouthpieces you are considering? I think it might be beneficial to look a bit more broadly (Denis Wick, Schilke, Warburton, Yamaha, Bach, etc...).

[Tallarry]

The problem is, there isn't any place in my country where I could try them... As you said, it's like a shot in the dark... I want to invest in a good mouthpiece because here it's hard to get one and now I have the opportunity to do it.
I want a good, quality mouthpiece. I want to use it at least 7-10 years... That's why I'm thinking about G&W and Greg Black. The max amount of money I can spend is about 150-170$. I also thought about the Hammond 11ML(125$), but the shipping was too expensive (65$)...