Thank you for your feedback.
The reason my hands, well more my thumbs, hurt is that I have odd thumb joints which means I can't bend my thumbs as far as most people. I have never been able to knit for really long periods at a time but it seems to be getting worse. This Summer I got chatting to another lady while on a train and she was explaining that she no longer knits as she can't get bone needles any more and the "modern" ones don't give. I started to wonder if that was my problem and I am hoping that wooden needles will suit me better.
I have never heard of Knit Picks or Crystal Palace,
I will go and look for them and I will also have a go at using circulars and bamboo to see if they improve the situation.