I have had M100 insoles for a few weeks (3 weeks) and I am cautiously excited... I am definitely seeing good results so far... In the morning my feet are not hurting and when I massage my feet, the feet feel .. well normal... A far cry from where I was before I purchased these insoles. I am not sure if it because of M100 but my lower back feels better and in general my legs, feet, back feel better ... even after my10K steps every day. I have purchased pretty much every brand of insoles but so far the M100 seem to be making a difference... Keeping my fingers and toes crossed... and cautiously excited !!