HERO's SupremeFX is just a marketing gimmick. It's actually a renamed Realtek ALC 1150. Both MSI and Gigabyte use the same audio codec. And actually they use better quality Nichicon caps like the ones on the professional sound cards. Performance wise they are all similar in terms of snr which is around 100-115. Actually only MSI manage to hit 115db snr with this codec atm. So they do a bit better. But not like a day&night.
If you want a better audio solution Gigabyte G.1 Sniper z97 offers by far the best audio. It has a quad core Creative sound core 3d audio processor and nichicon caps. Others are not comparable with this one. It's also cheaper than HERO, since Sniper's VRM is tad less powerful. But it's enough for air/water overclocking. But since you don't plan to overclock it's not important.
So all in all buy G.1 Sniper z97 if you want great audio and good overall quality.