I am currently using this cable between my Denafrips Gaia and Terminator Plus. It works very well, but the improvements are fairly modest compared to a relatively inexpensive hdmi cable that I used temporarily while waiting for this to arrive.
It is a definite improvement and I've certainly spent more for a less significant difference. But I think the Denafrips DDCs and DACs are not that sensitive to this particular connection.
Switching to i2s (instead of AES or SPDIF) between the Gaia and the DAC was a VERY noticeable improvement - much more so than upgrading from a cheap HDMI cable to the Tubulus cable for this purpose. But since it was an improvement, I've kept it in the system.