They have added a firmer section of rubber on the outside of the heel compared to previous generations of this series. Impact, weight and plyometrics, but don't run in them.
Pros
For a good fit, the size must be chosen larger. Great comfy shoes, hate that they don't make them anymore.
Cons
Limited Size Availability: Product is only available in US men's size 7.5, which may not fit those with a different foot size or shape.