Marcinkiewicz E9.1 Bobby Shew 1.5

This is only the second mouthpiece I have tried, but the one thing that hit me as soon as I put it to my lips was "Wow, this thing is really comfortable!". The shallow cup forces you into adopting good embouchure habits, so after a few hours of practice I still pull out the 7C knockoff that came with my instrument to squeeze out a few more minutes of practice time. It's very responsive compared to a 7C, and once you get used to it it's a very nice mouthpiece. With my chops well-rested I have no trouble accessing the limits of my high register at all, and the notes come out beautifully. I have even found that sometimes I'll be able to get a few extra notes beyond my limits. The low register is already quite tricky on my instrument (Startone STR 25) , and a MP like this certainly doesn't do it any favours; But it also doesn't really hinder you either. You just need to keep your embouchure controlled.

If you like comfortable wide-rimmed mouthpieces with a fairly shallow cup and narrow'ish backbore, then this is a pretty damn good one!

Can produce attractive husky merrow tone with less effort by using it, so it is nice for jazz use. To get such special sound just by changing mouthpiece was the first time for me, at first I erroneously suspected phisical/functional incompatibleness with the mouthpiece and my instrument at first. However, it was just my mistake. Because the expression of sound can be controllable actually, with less big effort or energy to control.
Conversely, to be simple, this mouthpiece is not for producing simple rich-resonant sound. Anyway, I am surprised by this mouthpiece that mouthpieces can change entire characteristics of sound and feeling of playing so much.