@milosz: I think they are concentrating more on headphone users and balanced headphones are neither popular nor very much better than unbalanced. PLus, as Currawong titled his review, this is supposed to be a 'No frills, no options, just great sound' DAC.

A non-oversampling DAC build by a Dutch company. Impressions thread here: http://www.head-fi.org/t/561674/metrum-acoustics-octave Review from 6moons here: http://www.6moons.com/audioreviews/metrum/1.html

Frequency range: 10Hz-20kHz Amplitude-frequency responce (AFR) irregularity within the frequency range: 0.3 dB Dynamic range: 110 dB Harmonic distortions: 0.002 % Intermodulation distortion (CCIF) 0.006 % Interpenetration of channels at frequency 1 kHz: -73dB Rated input voltage: 0.5...

I will see how these perorm in the long run.   EDIT:   I have had these for a few months now with a few hundred hours on them too. I use them with Meier Audio Stepdance portable amp and my laptop - a DAC to be purchased.   I have to say that in the beginning I was realy overwhelmed...