Russell Westbrook is very particular with his sneakers. So particular, in fact, that he had Jordan Brand remake its latest signature shoe to better suit him. In a profile on the OKC Thunder point guard at the New York Times Magazine, the team's equipment manager relayed a story about the Air Jordan 31.
Apparently Westbrook wasn't feeling the level of flexibility offered by the sole, and asked for an updated version of the Air Jordan 31 using the sole of the Air Jordan 30. He got what he wanted too, and has been playing in a hybrid design since October. The equipment manager, Wilson Taylor, gives Westbrook a different layer of cushioning by switching out the insoles by hand.
While it's pretty standard for NBA players to use custom insoles, it's another thing entirely for a player to request a remake of a new signature shoe like this.
The Air Jordan 30 and the Air Jordan 31 feature similar tech in their soles, using Flightspeed and Zoom Air cushioning. The designs on bottom are different though, with the 30's being decoupled while the 31 has a flatter, more standard ride.