Well I got the Great March II. I'm still waiting for a pair of XLR ICs to make A/B testing possible between the GM and the Apple TV's DAC. But I have A/B'd between the Apple TV's HDMI out, going into my TV, then out to my preamp...not an ideal comparison I know, but prior to the DAC, I used RCAs out of the Apple TV to the preamp, and compared that to the RCAs out of the TV and the sound was marginally better. (I assume the TV has some sort of built in DAC).
Anyhow, compared to the TV's DAC, the GM II is pretty great. Slightly wider soundstage, increased dynamics, and definitely airier. I also somehow gained what to my unscientific ears seems like about .25-.5 db in gain. This of course makes a true A/B difficult.
My ears are not educated enough to comment on things like jitter...maybe someone could clue me into what I might listen for?
One thing I've noticed, which I attribute to the increased soundstage, is getting the crap scared out of me by random sounds that seem to be coming from way across the apartment, which are actually coming from the music. :)
From a build quality standpoint, the GM II leaves a bit to be desired. The cutout for the solitary front power rocker is roughly cut. Also, the unit was opened at the factory to install 110V (they come 220 by default I guess) and either the case is misaligned, or it was reassembled improperly. The feet do not rest flat, but rather there is a slight rocking action. There's also a slight visible gap at the casing seam on one corner. Also, the feet also did not come with any rubber or felt padding...they're just bare metal. A quick trip to Radio Shack solved the lack of pads and the rocking, but nonetheless, it doesn't say much about their QC or attention to detail.
I saw the complaints of a hum from that fellow on another forum. I am happy to report I have no such hum. At full volume with no signal, the unit is virtually silent, using the stock power cable.
Will report back again on sound quality when the XLRs arrive.