Hello. I imagine you have now learned the difference between continuous flow and pulse flow and how pulse flow doesn't really give you the same as your home concentrator.
I have a prescription for 2L continuous flow for exertion and sleep.
I get by with my Inogen Rov 6 (set at max) when I go to store or am out walking. And I have flown with it to Florida. I had been tested and the result was that I did not need O2 during flying, but my oximeter told me otherwise! Fortunately, I had my Inogen with me and used that. Airlines want you to come with sufficient batteries when flying
I have Medicare and my provider provided the O2 concentrator for me when I was on vacation in Florida, so I had the stable concentrator for my night sleeping. I would not want to try sleeping with the Inogen portable even though they say you can