shooter

I've only tried one flugel in my life; a bottom of the line Jean Baptiste. It had so much back pressure, the air just seemed to stop somewhere between the mpc and the bell. Anyways, I'm making a trip to D.C. and try Chuck Levins' assortment out. I know that the mouthpiece makes all the difference, so I was wondering: Should I try several different mpc's for each horn that I try? Should the name on the mpc match the name on the horn? What i'm going for is a horn with a super velvety, mellow, tone for playing at church. Any advice is greatly appreciated since I know nothing about "horn trying" etiquette.