If you look at if from different angles, the ADI-8 DS MK III is a very good device and the sweetspot in terms of price/features.
And if you look at the technical specification, then the differences are not that big, quite close to ADI-2 Pro FS R BE.
https://www.dropbox.com/s/93xt00a95ktno … .xlsx?dl=1
Maybe also have a look at the different features of the products, some offer / have
- MADI / AVB option
- redundant power supply
- DB-25 and/or TRS plugs (so for some you need a patch bay, for some not)
- 19" rack form factor (ADI-2 Pro FS R BE and ADI-2 DAC have no rack mounts afair)
- per port selectable reference levels
- 4 or 3 different reference levels, some do not support +4 dBu, some do not support americal studio standards (+24 dBu)
- reference levels optimized for connection to HiFi devices (ADI-2 DAC FS)
IMHO it is not necessary for studio work to have selectable output filters on the DA chip (-> ADI-2 Pro/DAC).
"Nice to have", but maybe sufficient for the main monitor system and phones.
X10SRi-F, E5-1650v4, Win10Pro20H2, Cub11Pro, UFX+ (v0.9735), XTC, 12Mic, ADI-2 Pro FS R BE