I have been 2 pairs of the black assert 8’s which I have used for over a year. I can walk 4 miles or so about 4 days per week with no issues and can take them to the gym and do the stepper with them. They have always felt great until they just wore out. The 9’s bring back that support and comfort and feel even more comfortable than the 8’s when they were new. A good upgrade for me. Don’t regret this purchase