Very lightweight and comfortable.  It feels like I'm just adding treads to the bottom of my feet.  One of the few shoes that don't ever give me blisters.  Unlike other shoes, this shoe requires no "break-in" period, so it works well for getting them new before a trip/event.  They're very easy to put on and take off with their quick laces.  The only negative I have is that the tread doesn't last long.  This is inherent with their aggressive design.  What would be nice is if you could order the same shoe but with a longer lasting, less aggressive tread as an option (allowing customers to pick the tread that's right for them).  I'll be wearing these for the Catalina marathon and for hiking across Switzerland.