Hi Dennis. I am also interested in a continuous flow portable concentrator. I have my late mother’s Inogen One, but as you said, it is only pulse dose and can’t keep up with my needs unless just sitting still. I decided to look up this company’s reviews. They are not good. See here https://www.complaintsboard.com/meubon-oxygen-store-b152741 for one site that has customer reviews. In the US, we have the Better Business Bureau which grades companies. Here is the link to that site.
https://www.bbb.org/us/tx/houston/profile/oxygen-producing-equipment/meubon-oxygen-store-0915-90066503
I would keep looking is I were you.
Mindy