I do 7% in my eflow and have for awhile now. I've found that if I mix my xopenex in with the HTS I feel ok, and then I don't have to do two separate nebs. It does hurt my throat, though, so I sip on water throughout the treatment. One problem I've noticed is that the HTS gunks up the metal part a lot quicker than other meds so it needs to be boiled more/soaked in alcohol for longer, and even then it wears out. I try to keep a separate head for HTS so even if that takes longer, my other meds are still quick