I'm playing a Rudy Muck 17C mouthpiece on my trumpet. I just acquired a Conn Director Cornet without a mouthpiece. What cup size mouthpiece should I stick in the Cornet? Should I stay with something compatable with my 17C? If not, what effect will the difference have on my embochure, if any? I'd like to ask these same questions as it applies to a Flugelhorn.........thanks, tom