I have a moldable mouthpiece on my primary; very comfortable.. But I intend primary donate.I switched to a 40" Milflex hose (I have have been told by my LDS owner that the swivels haven't been holding up). Milflex hoses much more flexible than traditional hoses. If you are getting jaw fatigue I suggest a mouth piece that can mold to the shape of your mouth.
is this a ;problem for a recipient of "my" mouthpiece?