dumb micro bench of es5 vs es6 key value stores. combined set/get. paste into a console or `pbpaste | node` near you! I got es6: 57.397ms es5: 92.984ms for node 6.0.0

dumb-es6-bench.js

var m = new Map;
var o = {};
var value;

var rs = [];
var i = 1e5;
while(i--) rs.push(Math.random().toString())

var i = 1e5; console.time("es6"); 
while(i--) { 
  m.set(rs[i], "foo"); 
  value = m.get(rs[(Math.random() * rs.length) | 0])
}; 
console.timeEnd("es6")

var i = 1e5; console.time("es5"); 
while(i--) { 
  o[rs[i]] = "foo";
  value = o[rs[(Math.random() * rs.length) | 0]]
}; 
console.timeEnd("es5")