I'm training for a marathon.  I've been running with Brooks Ghost 5, which I find a great running shoe.  Recently decided to give these Glycerine a shot.

I wear Ghost 5 because I went through a shoe fitting process on which it was determined that I have a neutral gait. Mostly I run pain free.  After trying the Glycerin started getting knee pain (both knees) which makes me suspect this shoe made me pronate in some way.  The toe box is certainly smaller, having to buy the shoe one size bigger. Still, gave me a black nail.

In summary, after running aprox 40 Kms in total, gave up the shoes and went back to Ghost 5 pain free. The shoe has good cushing and roll over, but having to buy oversized feels somehow loose.  It's just not right for my gait and foot shape.