Hi, @pml I'm Scott and my wife was on home oxygen for several years of her war with brain cancer. She used an oxygen concentrator in our home. We found it reliable and easy to use. The model we had (I'm sorry, I no longer recall the name) was also nice and quiet and the background sound of it quickly faded into not being noticed. We also found a couple of things:

It tended to warm the room it was in so I placed it in the hall outside her room during the nights.

We still regularly checked her O2 levels with one of those nifty fingertip oxygen sensors.

We also kept a regular tank of O2 in our home in case of an emergency with the concentrator and/or a power outage, etc. We never needed to use it, but it was a constant source of comfort for my wife knowing that backup was there.

Let me know if you have additional questions on this,

Strength, Courage, & Peace