These are the best flip flops ever.  I bought them on the basis of reviews here on Amazon.  The Mush is a tradename for the very soft, almost squishy top sole that is about a quarter inch thick.  Beneath that, in the mid sole, is support you would never expect in a flip flop. Not sure about traction yet as still waiting for summer rains to arrive.  But I will spend a lot of time in these.