irenea8, one of those terrible reviews was mine! The unit itself is unreliable. If you are willing to spend a few hours/days, you might be able get the hang of what makes the unit tick - when it feels like it. Mine would run for a bit and then stop and then run again if I tipped it a certain way, then stop again, etc. And you already have a good idea of what kind of help or recourse I received from Omron. I had never written a bad review in my life, but considering people are putting their breathing in the hands of this machine, I felt compelled. I ended up purchasing a Pari Trek S portable nebulizer and have been very pleased. The Omron sits in its case unused.