The Ready State Virtual Mobility Coach is like having a virtual Kelly Starrett in your pocket.
You can crossfit in DCs, Vans, or All Stars
A couple of others to look at Altrazerodrop or Strike Movement
People can experience problems with Five Fingers as they ask alot more out of your ankle rom, heel cord etc. another thing that comes into play is what they were wearing prior to the Five Fingers. If there is a big difference between the 2 this is when the transition may not go as well.