@jsqt.
I'm not sure what you are using DSP for if you are not doing upsampling, but it is true that DSD upsampling is the most memory-intensive operation. EQ and headroom probably would not cause as many issues as the upsampling to DSD 64.
I want to experiment with DSP, in general, to see where it can take me. With the Zenith alone, I was unable to do that. With the sonicTransporter, I will certainly try upsampling.
I've spent a lot of time reading Roon documentation and blog posts. I realize I have A LOT to learn about the software, and with so many capabilities and options, I'll have to invest a fair amount time tweaking and comparing setting changes. I'm kinda sorta retired so I have much more time on my hands these days to play with Roon and, hopefully, take my overall system SQ up a notch or two :-).