I wanted info on the Mico as well and it was very hard to find. Now that I've spent a little time with one, I wanted to put some info here in case anyone else is interested.
First off, very happy with it, good simple build quality, and the sound is both defined and rich at the same time. If I had to pick one word - Refined. Smooth rounded low mids and bass, punchy high mids, like it reaches out and pulls you in, a 3D feel. Reminds me somewhat of the FMR RNP with the punchy thing, but the Mico is a little creamier (YMMV). It doesn't have the homogenized evened out feel of an API type pre or a BG1, but it almost sounds like there's a transformer in there somewhere. An interesting marriage of old and new sound concepts (to my ear, anyway) and certainly has broad applications, especially if you want a sound that can be gently aggressive but rich and open at the same time.
The A/D converter sounds very nice! Compared it to the converters in the 003 by sending an analog output from the Mico to an 003 line in at the same time as spdif optical to another channel. The difference was startling on an acoustic guitar. I knew the 003 converters were nothing great, but the Mico made the 003 converters sound like dogfood, truly.
The HMX feature is useful if you want a little tubey/transformerish thickness. Very little definition is lost and the clarity of the natural signal still shines through the added warmth. Nice to have another color in the palette if desired.
Haven't needed the phase adjust yet so no comments there.
Considering the sound quality of the pres and the super clean A/D, it's a great value. It has a subtle "glow" mojo thing going on that I associate with the sound of a high end pre, just enough character to be interesting and still provide excellent reproduction of the source.