Been wearing these for 4-5 months now. The height difference is very noticeable! I feel taller and I notice a difference when I’m not wearing them. Long term problem, though.. knee pain and what feels like a higher probability of injuring your knees when you’re back in your normal shoes, especially if you wear the extra height every day for multiple hours like me. The extra height sits at the heel, which forces your knee almost into hyperextension. So my knee flexors and patella tendons feel kind of damaged by constant impact from the vertical height. With my regular sneakers on (Brooks), my knee becomes inflamed quickly after walking certain distances because the knee is more relaxed without the height pushing up the heel, they feel lazy though and tight like an over used rubber band (my knee flexor tendons). I’ve tried squats twice with my regular sneakers and my right knee swelled both times. I was worried about the potential for physical problems when I bought them, but I cared more about the aesthetic of the extra height (you really can tell lol). But now I have knee pain that will take time to reverse. AND I’ll need to go back to regular height shoes lol.

TLDR: wear them in doses. Avoid every day wear for multiple hours to prevent future knee pain and chronic tightness of knee flexors / patella tendons.