Hi Fan- The 6 is more open at the tip than the 5. Need to push a bit more air or use a bit softer reed, but not much - they're close. If I remember correctly the Meyer 5 has about a .085 tip and the 6 has about a .095 (the same as a Link 7?). You can check for sure at mouthpieceheaven.com - I think is where I saw that chart. Incidently, the current production Meyers might not thrill you as much as what you're expecting, while one of the vintage New York Meyer pieces will cost quite a bit. You might do well to read about Fred Rast mouthpieces at rastmusic.com and Patrick Springer mouthpieces at springermpc.com - - - Ralph Morgan also makes a quality hand finished hard rubber piece. And I've heard good things about Jody Espina - but have no first hand knowledge. Good Luck.