they are definitely different sounding - the TEAC having a more laid back and darker presentation
that sounds like an adequate description of the differences to me, and would make the teac preferable to many who might lean towards the yulong D18 or eastern electric DACs.
But you still own a Teac... who also make every other cheap consumer item in the world. Even if it sounded decent that would bug me forever....
as someone mentioned, teac esoteric is their high end line, and their ceramic driver $20k magnesium driver speakers got a serious rave review in stereophile for world class sound and freedom from distortions. yes, teac makes consumer gear, but they also make studio recording gear where lofi is NEVER an option, and back when they were still making cassette decks, theirs had the absolute best specs, particularly in the wow & flutter category. if you want to use the japanese consumer product analogy, honda makes cheap civics, but also made the NSX which was reviewed as the best balanced supercar in the world plus they at least make engines for formula 1 racing too. if anything, being a giant corporation gives teac a huge advantage in R&D dollars.
biases are hard to shake. back when the sonic impact amp was first released, no one wanted to accept that a $15 plastic amplifier could sound "tubelike" or even "high end". i'm having to shake my own bias against NAD after the terrible synergy my receiver had with soft dome tweeters as the general consensus seems to be that their M51 DAC is one of the best in the world. gear is what it is, and not what we label it in our heads, but i still can't get past how fugly the teac DACs are. LOL red LEDs always look cheap and tacky to me reminding me of the 1st generation made in russia giant digital watch i was given in the 70s. i don't like red LEDs one bit.
if teac reboxed the DAC in an esoteric line with an appropriate high end looking aluminum enclosure with blue or white LEDs, i might consider it. green LEDs look cheap to me too, but red are the worst. i'd have to tape over them which creates a different kind of fugly.