In experiments with PCs on another forum we have come to the tentative conclusions that one crucial factor in computer audio is the power on the motherboard. In moving from SMPS to linear to battery power, a commensurate & noticeable improvement in sound was noted. In further separating the battery power into 12V, 5V & 3.3V feeds, another improvement in sound was achieved.
The CAPS 3.0 runs on battery power.
Given that Vincent just said his preference is for conversion isolated and re-clocked outside of the computer, I don't think you disagree on this point. Power supply impact is, of course, another question.
But I2S Pro reclocks using the DAC clock. I'd be shocked if this were inferior to outboard reclocking, since folks using I2S Pro report getting the best sound out of their MSN DAC. In fact, the MSB should be switched to reclocking mode for synchronous sources (and asynch USB), which reclocks inside the DAC as well, so with MSb reclocking outside the DAC is never the best architetcture.