I love my Schilke, and even though I can play A above high C with it, it is uncomfortable playing it sometimes. I am considering having it gold plated to add some cushion to it. Also thinking about getting a 13A4 and trying that. Maybe a smaller size will bring benefits?? Who knows, but I'm looking for comfort now. On a good day I can play the C above the 4 ledger lines and a space A with the schilke, but that's very rare. The chemistry has to be just right. I find that I can hit the super C when I do a light practice session consisting of long tones, slurs, chromatic scales the day before. I think I'm going to sell the Parduba, because I'm just not feeling it at all. I've only had the schilke for about 13 months. When I switched from a bach 3c to the schilke 14A4, I improved instantly. I truly thought that it was the mouth piece I would stick with for years.