Thank you everybody for contributing to this site. It helps so much having such a wealth of other peoples' experiences and knowledge. It is invaluable. I have learnt so much and it is so reassuring to know how other people cope.
I have now got over a lengthy chest infection and have been given the Inogen One G2 concentrator, I did a trial run in the car yesterday and coped ok. My freedom at last.
I wish everyone a wonderfully Happy Christmas and better health for the New Year. Thank you all.