Happy you are enjoying your setup!
Curious though - in your signature you are listing the Mojo paired with the Cayin N3 - does it really sound different with the xDuoo X10T II?
I'm using the HiBy R3 as transport and absolutely love the stackability with my 3D printed case and box.
But if the xDuoo X10T II is sonically really better, I might have to think about it....
Sorry for taking a while to reply to this, but I wanted to really go back and forth between the N3 and X10TII with some of my most well known test tracks, just to be really sure. I went back and forth between the two listening to select songs from "Awaken, My Love!" by Childish Gambino (24-bit 96kHz), Jolie Holland's "Wine Dark Sea" (24/96), and the SACD remaster of Rage Against the Machine's self titled album in 24/192. All listening from Cayin done with a HiBy USB C to 3.5mm coax cable; all listening from xDuoo from 3.5mm coax output using included xDuoo coax cable.
To answer your question, yes, the xDuoo unit is significantly better. I'm even more confident than before when I say that this is the best I've ever heard Mojo sound and puts it in the category of one of the best DACs I've ever owned, that's not even to mention that it has enough juice to drive hungry planars like the ZMF Blackwood. The most obvious difference for me is in the blackness of the background, which translates into better low-level dynamics and transient detail retrieval. This goes across the entire frequency range, but the bass in particular is noticeably deeper, faster, and more dynamic. It's generally more focused and full-bodied through the bass and mids--not quite R2R-like body, it's still clearly D/S, but sounds full in a way that I personally haven't heard D/S do before. Percussion and cymbals in particular are perfectly clear and resolved--to my ears, snares are one of those things that cheaper digital products find a hard time representing naturally and clearly, as they are complex waveforms that can easily get smoothed over. The N3 does a decent job with snare drums, much better than my phone, as you can start to hear all the tiny little details.... but the xDuoo is on a different level and absolutely nails the snap, the reverb, all the little details that make each strike of the drum unique--everything is there.
I was pretty impressed with how much more detail and dynamics that the N3 was able to squeeze out of the Mojo and was honestly a bit worried that the xDuoo might not even be able to do that much better, that the N3 was already pushing Mojo to its limits... but I was wrong. I am floored by the way the combo sounds. It is so engaging. I can't speak to the HiBy, and the X10T definitely doesn't stack on the Mojo as nicely, but sonically it is a stunning combo. YMMV but my guess is that you will not be disappointed.
Edit: Just wanted to include that I feel the xDuoo unit also wins in terms of usability and general feel. The capacitive touch buttons on the N3 are so easy to mis-strike and can be very annoying, whereas the xDuoo has physical buttons so zero issues with that. The N3 has a plastic case and is a decently attractive/good feeling unit, but the X10T with its aluminum body and physical buttons has a much more premium look and feel. It's only slightly larger than the N3.
I did notice the other day, as a con to add to the list, that EQ did not work for 24/96 files, which was a bit disappointing as I'd like to pump the bass up while listening to Purity Ring's "Another Eternity" in 24/96. I'm assuming that, like the N3, there's a cutoff in sampling rates over which the unit doesn't have the processing power to add EQ. Disappointing, to be sure, but not critical... I can always put on bassier headphones.
