I developed sever allergies to something later on in life (still trying to pinpoint exactly what, all I know is I get random flare ups), and NasalFreshMD is the one you want for serious sinus issues. It's bigger than either of those other devices though. The Navage has this proprietary pod thing going on so either you but their pods or you get a defeat device but the NasalFreshMD just has an open port for you to dump whatever brand of salt (including NielMed refills if you like their formulation) and however much water you want into so is much easier to use. It has three speeds to the Navage's one. (Not sponsored, just a happy user.)