Wildman,
The mellow yellow is a great call! As for frame size, I am trying to figure out a way to have customers measure their palette to ensure they get a proper fit.
This call is similar in ease of use. The break over is very smooth on this call and takes little effort. I ended up with a .004 latex on this call to give it a deeper tone and it also allows the volume to be cranked way up without the call locking up.
I also have a recipe to make a call very similar but allow bugling.