Laskey 30H vs. Laskey 30G mouthpiece

[ThaZhangsta]

I've been using the 30H (Helleburg shape) for a year. I've recently discovered the 30G mouthpiece with a Geib shaped cup. The description for the 30G on the Laskey website explains that the 30G produces a more brilliant sound and is good for rotary tubas.

I play on a BBb miraphone with rotary valves.
http://www.miraphone.de/en/en_modeldeta ... 7&v=1&l=en" target="_blank

Does anyone have experience with either of these mouthpieces? I'd also like to know how a Geib shaped cup is defined.

Will this be a beneficial switch.