TEAC NT-505 - How good is it?

Not for me, but I don’t have separates so moot point for me I guess. I use an audio research integrated amp where the preamp portion of it is not bypass able. 

As for DAC/Preamps...I hear the Myteks have excellent preamp capabilities

I bought my Teac NT-505 in May 2019, sound and features are higher than what I expected. Network streaming is not as what I expected, it is always cutout, two days ago the network card is not responding, replacing cables, reset to factory settings, reloaded the newest firmware V1.22 still not fixed the problem. Waiting for authorized dealer’s response for next step. What a shame!!!

I ordered the NT-505 in August and received it two weeks ago, after an extra corona wait I was told. No problems so far. Ethernet playback of my high res files, usb playback (flash drive, also from a hard disk, usb-conneced), and streaming from Tidal - it all works fine. Lumin app also, after getting to know it. I had an Ipad laying around, and controlling the Teac from the Ipad is an unexpected bonus. Sound quality: it is certainly a big step up from my former Squeezebox solution, as it should be. Does it rival my analog rig? No. Or at least, not yet (it may need more burn-in). Today, I noted that it does sound better bypassing the volume control ("fixed 0db", rather than "variable"). More assertive, direct, less ’polite’. My vinyl rips (DSD files) sound closer to the original LPs.

Just in case any of you are having issues connecting to “net” using your NT505, there is an issue with one of the boards in the unit.  My 505 developed this issue within 3 months of buying it.  Really had a hard time getting approval to have it repaired, but finally did.  Now it’s great.  For a while I thought this might be a door stop, but since the factory service center did the repair, it’s excellent,
IMHO, use Adams Electronics in California if you have issues with your unit.