The 47 Labs sounds more realistic. It's hard to nail down exactly what it does, but I cannot enjoy the sound of the HG Super Silver's anymore in comparison to the OTA and before I really liked them. Everything for me is based on such comparison and once you hear something that clicks more, it's hard to go back (because now you know). The IC's are easy to make if you bevel/taper the insulation a bit when inserting the cable into the black part of the IC (this is not needed for the white part). Each plastic RCA comes in two parts. The kit has two short examples already made up for you to copy. $600 is a lot in one chunk, but considering that you get killer speaker cable plus three sets of IC's (to grow) it's also a very frugal purchase in the long run. Before, I replaced a pair of Harmonic Tech Truthlinks with the HG IC (the HG's were more dynamic, more forward and had finer detail). The OTA has even yet finer detail and a more realistic portrayal of everything from the bass on up to strings, bells and cymbals. It is not a slight improvement, but a major one when either the SS or the tube amps are used.