To me it can make sense to combine streamer, DAC, and preamp in a single box (then just add a power amp and speakers ... or active speakers). That way you're paying for just one chassis and you reduce the number of interconnects. This "integrated preamp" is a modern, digital alternative to the traditional integrated amp. Many products are available that combine 2 or 3 of these functions. Prices range from ~$500 for Bluesound to nearly $40K for the T+A SDV 3100 HV.
I have owned the BS Node 2i, the iFi Pro iDSD, an ultraRendu (streamer/NAA only, no DAC/preamp), and the Matrix Element X. Lately I've settled on the Matrix Element X, which has an excellent DAC, WiFi/ethernet streaming, decent input switching functions, and very good volume control. As far as I'm concerned, all these devices perform the ethernet streaming function about equally well (all else being equal, or nearly so). As for the DAC per se, I'd find it challenging to isolate the contribution it alone makes. FWIW, in ASR testing, many devices (including the Element X) have measured better than the Node 2i.
https://www.audiosciencereview.com/forum/index.php?pages/Audio_DAC_Performance_Index/
I have owned the BS Node 2i, the iFi Pro iDSD, an ultraRendu (streamer/NAA only, no DAC/preamp), and the Matrix Element X. Lately I've settled on the Matrix Element X, which has an excellent DAC, WiFi/ethernet streaming, decent input switching functions, and very good volume control. As far as I'm concerned, all these devices perform the ethernet streaming function about equally well (all else being equal, or nearly so). As for the DAC per se, I'd find it challenging to isolate the contribution it alone makes. FWIW, in ASR testing, many devices (including the Element X) have measured better than the Node 2i.
https://www.audiosciencereview.com/forum/index.php?pages/Audio_DAC_Performance_Index/