Your connectors probably aren't much more expensive than this, seeing as you will be plugging into the back of a motherboard. So don't go wasting money on $50 RCA adapters no matter how hilarious the Schiit audio manual is. These cables will work fine enough. If you lack any clarity then purchasing a DAC will do a ton more than purchasing $50 RCA to 3.5mm adapters ever will.
So unless your motherboard has platinum-plated connectors, yeah, go with these. They also arrived within 1 day!