I have the pro neb by Pari, and prefer it over the vios and Ombra. I think the higher the psi in the compressor part of your system the more force the mist comes out in the cup, which in fact is the nebulizer. Some cups break down the medication/saline into small particles of mist to aid into getting it deep into your lungs. From my experience only I’ve learned that some cups work better and faster than others, the same goes for the compressor part of the of the system. I’ve been told my BE is severe, and worst in both lower lobes in the back part and the right middle lobe. I like everyone else has had to experiment with different types to see which works best for me. I currently use the pro neb compressor, and the Vyaire misty max cup for my bronchodilator, I then wait 10-15 minutes then do 7% saline into the Pari star cup or LC plus cup, and intermittent Autogenic Drainage while doing the saline. All this in the a.m takes about an hour, but I feel it’s worth it if it helps me feel better throughout the day.