I have been very careful not to bring up SW1X unless someone else does. The reason is fairly simple-I just don't feel qualified to make qualitative judgments as to competing DAC's at any price level. But I auditioned the SW1X 2 SE with the USB option and it blew me away. So much so that I utilized the free trial program of the distributor and bought a SW1X DAC 3 Balanced. I am very happy with it too but it is not $7,000 better than the SW1X DAC 2 SE. It is perhaps 90% DIFFERENT and 10% BETTER if that makes any sense. But here is my overriding message to you-since you brought up SW1X-try one and see for yourself-they are legitimately great, IMHO.
Keep in mind fwiw that Michael Fremer auditioned the basic SW1X phono pre and raved about it. He then ten or so months later auditioned the equivalent phono pre as my DAC III Balanced and also found the difference to be minor.
On the plus side, ALL SW1X products are hand-built with utmost care and built to last. I don't pretend to know if Slawa has truly innovated from the AudioNote products that he has clearly emulated. There are minor differences. The R2R chips used by AN at each price point differs from those of SW1X. Slawa wrote me several times as to his design philosophy-a great DAC should be built more akin to a power amp or stout pre-amp with a robust power supply and careful attention to the input and output stages.
I like knowing that my DAC was purpose-built. It shares little or nothing with other products in SW1X's line-up. Parts are not just swapped from from one multi-purpose bin to another as is standard practice for so many brands of audio components.
My final word on SW1X (in this thread)-the sound from my DAC 3 Balanced, assuming a good source is utterly relaxed, detailed, and organic. If I were forced to knock it down on one aspect it would be that it perhaps does not suit rock music as well as others I have heard. I am referring to something with bass slam and dynamics such as (dare I mention them) LCD Soundsystem stuff. I am happy with it even with rock but if someone were to say that it is weak in that area, I would understand that view.