charles_dunkinFrom some quick research, people suggest against the Yulong u100 at it's native price point of being 225+. From what I could tell as well, I believe the u100 was first introduced/made in 2011, so that means it's quite old tech.
Unless you're dying for a dac/amp, I'd compare the o2 to the e17... After research, I know I'm putting the u100 out of my mind.