OK Everyone I just started using Tobi again this month. I havent used TObi or Colistin since last spring thus I havent been using the Pari LC Plus. I was using my Sidestream. The ONLY input I am looking for is about any experiences with muscles tension from breathing thru it. I know a lot is from my biting down on it since it fits differently in my mouth. Last night after using it I could feel the tension go from my jaw down into my shoulder where muscles issues already exist. I feel a difference for the better using TObi, but dont remember having this issue with the neb cup before. Granted I didnt have the shoulder/muscle issue during my last use. I am just curious is all......