I use the FiiO7 and they sound awesome.. obviuosly a lil bulkier to travel with but sound quality improves by about say 30%.. volume only increases by 10%.. but sound stage is a significant diff. good luck

The ATH WS70 are incredible, you will love them! honestly. Fun is the word. I love Hip Hop and Electronic so I love good bassy clear headphones and I can say that the sound is unreal...you will not be disappointed! only thing is that they're made in China, but the sound is very much Japanese...

I'll be as honest as I can.  I have a FIIO 7 driving the WS70 whist on the go with my Itouch and all I can say is "these cans are Aweome fun!!".  They deadset feel like they bounce off your ears!! incredible bass and highs, very impressed! Yes they do feel quite tight on the ears at first but...