Javascript ES6 to ES5 Transpiler

When you are so eager to use ES6 features but you know that most browsers not yet implement all ES6 features completely (that's why there are also HTML5 pollyfills). Here's the list of transpiler to convert Javascript ES6 to ES5:

• Google's Traceur Compiler
• Google's Caja (client-server)
• Babel (if not sure, use this one)
• Termi ES6 Transpiler 
• full list here and here (with pictures)

Almost 2 years ago comparison between Babel and Termi. Oh and yes, you can use Babel with WebStorm.

Note that every transpilers (CoffeeScript, TypeScript, Elm, Haxe, etc) suffer the same problem: compile duration (hey, one more thing to do [=minify] before testing/deploying) and hard debugging (easier if you use source maps, only for JS transpilers, I don't know if these things exists for transpiler for other language). Still I wish for wAsm to come faster. Btw I learned ES6 just for react-native-web, otherwise I would always still stick with ES5.