I'm listening to my NFB 10es2 Vali and W1000x combo! WORTH IT, the vali just does EVERYTHING I wanted it to do with my w1000x and NFB 10ES2 [acting as a fixed line out dac]
:D listening to some dub step atm and that SUB BASS... me gusta! Sadly I've found the w1000x is the one headphone I DO NOT like to EQ... I can never settle on a good eq setting, that said though the color teh Vali adds is very complimentary to the w1000x :D
But again the NFB10ES2 is a very cold and clean dac, it combined with the Vali... is very good!