Since you are already falling in love with the Luxman DAC, I'd bet that you'd be very happy upgrading to the M10X. I had an MC452, had a Luxman M600a, auditioned the M900u, and currently own an M800a. I really liked the MC452. I could live with it forever if I had to. Their autoformer amps have a distinct tone and texture that I find very enjoyable, natural, and unique. That said, if I put on my audiophile hat, I find that the Luxman gear is just more refined and nuanced with more detail, air, microdynamics, speed, but also gorgeous tone. There are many lifelong diehard Mac fans, but the praise is more about musicality than technical prowess, so I think it depends on the kind of audiophile you are. Since you like your Magico speakers a lot, I think you will really appreciate what the Luxman gear brings to the table.
Also agree that Mac isn't well regarded for their source components. I had a C8 pre with DA2 and found the DAC section to be okay, a decent implementation of the Sabre chip, but nothing to write home about.