thanks for all the replies in here,
just wanted to check back in and confirm (for possible other users) that the X300 works.
I have nearly no problems running the Ettus X300 via ethernet at 50MHz BW. Audio is clear and according to SDR Console only delayed by about 20-25ms
(Image in full res: https://i.imgur.com/7PkOmyZ.png)
The device has the "HG" firmware flavor flashed, using a "10Gtek SFP+ to Fibre transceiver"(inserted into SFP+ Port 1) connected to a MikroTik CRS312-4C+8XG-RM.
The PC running SDR Console is equipped with an Intel i9 7980XE and is using an RTX 2080Ti for the CUDA waterfall.
Network bandwith is about 1.7Gbps at 50MHz and about 650Mbit at 25MHz.
SDR Console was able to find the SDR (after ofc. reflashing the EEPROM of the X300 to change the default IP of the device) by just telling it to search for Ettus Research devices.
The only bug I noticed was that the waterfall sometimes stopped working after using the zoom feature to zoom in/out, happens mostly when using a high BW(>20MHz)