I am not familiar with the Aqua DAC, but have enjoyed my PS Audio DirectStream DAC, purchasing mine just after it was released.
One thing I very much enjoy about the DAC is that, because it's designed around an FPGA and not an "off the shelf" DAC chipset, PS Audio has released a number of firmware updates (which are very easy to apply), and every single one of them has improved the sound quality...like getting a "new" DAC once or twice a year.
I also find the support at PS Audio to be excellent.
One thing I very much enjoy about the DAC is that, because it's designed around an FPGA and not an "off the shelf" DAC chipset, PS Audio has released a number of firmware updates (which are very easy to apply), and every single one of them has improved the sound quality...like getting a "new" DAC once or twice a year.
I also find the support at PS Audio to be excellent.