DH Labs would also be my recommendation. I bought one for my Rockna server/dac combo. I later tried a RAL cable. Both units have 2 i2s connections, so it was pretty easy to go back and forth between the two cables. At first I thought I heard an improvement with the RAL cable, however I did another comparison after I had them both for a while and really couldn't tell the difference. I chalked that one up to confirmation bias.
