Very comfortable. I would recommend to go at least half a size up.

It ruined my toe and ruined my marathon performance. This shoe has wrong sizing and badly designed toe box and you need to be careful.. bought 2 so far and both ended up in the trash. First bought my usual size which was perfect in pro 3 version. That ended up too tight at the toe box. Then I sized up, felt good at the toe box in the store but in a long run, the shoes is big so the toe slides down and hits the end front of the shoe. I had to stop running towards the end of my marathon, ruined my performance and ended up with a black toe one more time. Worst shoes ever from that aspect. I looked on line for a pro 3 and bought that again. Adidas please fix this as otherwise it is a great racing shoe. Hope you’re listening.