My niece has cystic fibrosis and I attempt to study the subject as often as possible. One area of study that I conducted - compressors and nebulizers.The sidestream nebulizer is excellent as well as the Pari nebulizers, but it is the proper nebulizer and compressor that are important. The cystic fibrosis foundation conducted a study of nebulizers and compressors at the University of Washington a few years back in which they stated that a person should find a nebulizer with pre-determined limits and then to purchase 2 or 3 other compressors to do the job.These are my thoughts based on my own studies. The sidestream nebulizer is very good, only wasteful. The Pari LC Star nebulizer is a breathe enhanced system, when you breath in a vent opens, allowing for air to enter the chamber, helping the nebulized medicine to flow better into the lungs. When you exhale the vent closes, causing pressure to build within the chamber, preventing the nebulized medicine from flowing into the chamber, decreasing waste. A small nozzle opens at the top of the nebulizer, which opens for your exhaled breath. Another important feature with the Pari LC Star nebulizer unit---78% of the particles are below 5 micrometers in size, 34% of the particles are below 2 micrometers in size. This is important because the smaller airways (alveolous sacs) are all below 2 micrometers in size, this is where the oxygen is placed into the blood stream and the place that virus' and bacteria prosper. By using a nebulizer that will get the medication to its location is important. The Pari LC Jet Plus pre-determined limits are 50% below 5 micrometers and 20% below 2 micrometers in size. A good example....Pseudomonas aeruginosa bacteria average between 0.5 - 3.0 micrometers in size.The compressor unit is very important. Hospital wall air is 50 psi (pounds per square inch), the Pari Proneb is only 23 psi when the nebulizer unit is attached. You need between 12 - 18 psi to breakdown Tobramycin so the nebulizer unit can work within the pre-determined limits. On the other hand "Pulmozyme" which is cold, thick and viscous, you need a nebulizer that can go up to 50 psi in pressure. Pulmozyme needs the compressor unit to have a constant pressure between 35 - 45 psi to properly breakdown the medication, so the nebulizer will function within it's pre-determined limits.Invacare Mobilaire 50 psi - is adjustable, meaning the pressure can be adjusted from 1 psi to 50 psi, based on the medication you are nebulizing at the time.Pari LC Star is the best in my opinion, but the Sidestream nebulizer could very well be the best for the adult if the adult inhales, holds their breath, while covering the hole so medication is not lost. If I were to make a choice it would be the Pari LC Star nebulizer and Mobilaire 50 psi compressor.If you should have any other questions, I will pay attention to this website.