I agree with this statement. I don't care how rubbery soft the bit is if the bit is not comfortably shaped. I ordered 4 Castello's at the same time because I thought they wee beautiful and had reputation of being great smokers. They all felt awkward and unstable in my teeth, so eventually they were all sold for a considerable loss...I'm mostly good with them all as long as they are made correctly.
I suppose I could have just had stems made to my liking, but none of them were "dropping my panties" in the smoking department.