I've been playing the Stage 1 mouthpiece for about a week now, so some thoughts:
Super comfortable! The intonation seems spot on, just plug it in and play. It has a nice bright sound, probably not something I'd use on a classical gig, but the high register is easy and singing. It takes much less effort to play up there than with my Purviance.
It is pretty shallow for me, I have big lips, but I think I can probably get used to it just for the ease of playing it allows.
And it looks cool.
http://www.newyorktrumpetcompany.com/stage1mp.htm