Unless the boards are identical enough in other areas, then I wouldn't choose one over the other, based purely on which has the supposed superior audio, if it means getting a lesser board feature wise.
Quality of onboard audio can be addressed by adding a sound card, internal or external, or a DAC.
As theforce says; the chip/codec may be better, but it depends on the implementation. In other words, you can't know for sure just by looking at what Realtek codec is used. Some motherboard audio can work perfectly well, another may be susceptible to interference. That is not decided by which Realtek codec is used, but by the implementation by the board manufacturer.
Not just that, but the choice of other system parts may have an impact. That is almost impossible to account for. I've seen someone with perfectly working motherboard audio, go from no problems, to having interference, just by changing to a different graphics card.
If you miss out some other feature, just to get a better Realtek codec, which for whatever reason ends up being poor, then that's a shame; when adding a sound card or DAC is easy and doesn't have to cost a lot.
