As a DAC only and feeding my Pico Slim, and ignoring all else but the sound, I think I slightly prefer the little bit of extra transparency and space of the Hifimediy SABRE DAC over the UD100, but it's pretty close. They both beat the crap out of my old $49 Headstage DAC cable (PCM2706 all by itself), and either one of these would be an excellent inexpensive DAC upgrade for something like my 3MOVE, XM5, or EF2 amps with older built-in PCM2702E JPN DACs in them. The line-out sound quality of these $50 DACs comes very close to the line-out of the uDAC-2 SE and Audioengine D1 that cost times as much, but when driving headphones they fall behind and that's where your Stepdance comes in.
If I absolutely needed the smallest possible DAC to feed an amp, I would not have a problem with picking the UD100 over the Hifimediy if that one was too big. But I just can't think of a time when that would be an issue for me, and I like to consider the extra features that I might be able to use some day. Note, the UD100 does sound more spacious when driving an amp than when driving a headphone directly. When driving a headphone it just sounds more compressed and bland, but it's really clean and more lively when driving an amp. So keep that in mind.
I will be trying these DACs with my iPad 3 and camera connection kit, and if they both work the HiFimediy might still be a better choice because of the short flexible cable that would prevent the DAC from acting as a lever in the CCK that's plugged into the 30-pin jack.
Yeah, I would prefer to use these as a DAC only, but it's nice to be able to drive a headphone in a pinch. That wouldn't be a long term solution for me. Even a cMoy plugged into these DACs should be a big upgrade.
