Dac bypass seems like no problem with acss gain module. However, using headphone out instead of rca outs could make some negative difference (even somebodies say not) And off course don't forget the smaller transformer.
I think price difference mainly comes from western and Japanese parts inport costs. Basic version looks very close to version A. Still, placebo effect works. If you buy a basic version, you probably can't get full satisfaction. That is...