I have been using the M100s for about a year and I am so happy with them. I have been wearing orthotics for most of my adult life.
A couple of years ago, I had a new set created by my podiatrist to help with numbness in my left leg and back pain. They helped some but not entirely so when I saw an ad for the M100, I thought I would give them a try (they were a whole lot cheaper than the ones my podiatrist made).
To my amazement, the M100s completely solved my problems. Since then, I have relegated my expensive podiatrist-created orthotics to my sock drawer and have purchased M100s for every pair of shoes I own. Thank you for an amazing and life-changing product.