Monitor controller is the DAC any good?

[1DMF]

I've been puzzling over whether I need an audio interface or just a monitor controller.

I currently run SPDIF via optical cable from onboard ASUS mobo sound via Realtek ALC1150 8-channel audio codec with high-fidelity OP AMPs and a noise-isolated PCB and 112 dB and 104 dB SNR.

I was considering getting something with opitical SPDIF so I can still output from opitcal cable , but do I need to as they come with USB audio interface functionality.

I had narrowed down to...

Audient iD22
Mackie Big Knob Studio+
SPL Crimson

I see praise as well as complaints about all three, plus the SPL is a tad expensive and wonder, if I just use SPDIF, is the Mackie a good option as I like the idea of being able to power more than one set of monitors via A/B switching and mono.

Or might I as well get the Audient and not run SPDIF?

Perhaps if I scrap SPDIF, a second hand SPL Crimson is more affordable.

I really wasn't planing on spending so much on an interface, and so had rulled out an Apollo, RME etc.

Your advice is apprciated, as i've never used an interface before what with my current monitors being passive and came with their own amp.



Thanks,
Craig.