I've had these runners ~3 weeks now. Maya helped me (on the phone) get the right kind (cloudace), and the right size. She also helped me when delivery went sideways. The runners themselves are comfortable. They feel stable. I'm 61, & borderline obese, so I thump along like a rhino through the underbrush.....but I don't feel any pain in my (previously injured) knees. I'm very glad I got these....I don't know that I could do it in an 'ordinary' pair of runners. The ones i tried on at a local shop felt wrong.