4 x PCM1704 would put it in the Reference 5 and 9 range. Reference 7 and 8 got 8 x PCM1704.
The I2S input is very nice though. Once I asked Kingwa the possibility to put I2S input in his DAC and he said doing so will have to diable all other inputs.
I always think of buying a cheap Chinese media player and hack the I2S output to connect directly to the DAC. This saves all the troubles of using computer as source and the USB connection trouble.