My buddy Rex says his new STM is beating his L.I.O. with AVC in almost every way, especially in detail and soundstage. Now he is hesitant to trade his AVC in for the DHT on his LIO.
For those that is drooling over the LIO but cannot afford it, look at Tommy's STM.
I had the full 30 day trial with LIO last August/September - with DAC, AVC/Tubestage, and the mosfet amp. I had Vinnie configure some custom line inputs direct into the mosfet amp and a little switch - so I could properly A/B every one of the modules against my other components. I found the DAC and AVC/tubestage to be highly highly resolving, but not as tonally or harmonically rich as my Lampizator level 4+ DAC or Dude tube preamp. But that could have been a matter of taste for some. LIO was very high quality performance here and quite competitive with top shelf electronics if you ask me.
But the mosfet amp itself was nowhere near the same level of resolution, refinement as my Line Magnetic 518 amp bypassing its own preamp stage. I would consider the mosfet amp the weak link in the LIO, but LIO could be highly competitive as a DAC/preamp with the right configuration and tube selection. And I have no doubt that the DHT upgrade is a big one - because I've heard what that kind of output stage can do when I upgraded to the Lampizator Big7.
So, I'm not surprised to hear the STM's beat out the LIO amp stage, but I'd encourage Rex and others to try other amps with LIO to see if you like how it compares to your other DAC's/preamps.