A yr later as well & owned one since winter. I've noticed the oxygen concentrator DOES slightly help my jolts/spasms while using it, slowly breathing in at pace it'll feed me so I only breath 90+ % oxygen. Heats the bedroom which isn't welcome during summer, but winters are warmer with it. I sleep a bit better as well. All positive effects end once you stop breathing it so this leads me to believe blood flow IS an issue. Increased flow would increase oxygen right?