To the above we might as well add the Zanden and the Audio Note 4.1x Balanced (we carry Audio Note).
I agree with mikeL that one can tell quite a bit about equipment at shows, especially in excellent sounding systems (one can hear deep into a system a lot more if one's ears do not have to shut down as a result of some nasty noises the system shouldn't be producing).
However, evaluating equipment is like evaluating a marriage partner: they may look and sound good, be entertaining, seem to have lots of depth, and so forth, but it is only after living with them do you really know what they are like. an even then, the system environment has a huge impact on how they will perform.
My point (yes, finally getting to it now...) is that these are all good DACs, I have heard all of them sound exemplary at sometime in the past in one or more specific systems (except the Goldmund DAC, we have only heard their single box player). All of them will sound great in just about any great system - the system will not have to be crippled in order to make the digital sound palatable. It really comes down to flavors, technology, features and cost.
Does the DAC strive for massive amounts of delicately rendered detail? Does it strive for an analogue sound? a natural sound? a pure sound? Does it emphasize bass? dynamic swings? continuousness? Each DAC seems to have a different purpose which seems to be a mixture of one or more of these flavors.
Does it use vacuum tubes? Does it have a variable output stage that can connect directly to an amp? If so does it have inputs in order to function as a full-featured linestage? Does it support SACD? Does it have lots of options to tweak the sound? Does it try to deal with vibration control or is it completely up to you to use external tweaks? Is it upgradable (and do you care)?
Does it have a associated transport that has been optimized to mate with the DAC? Does it look cool? :-)
OK, never mind, they ALL look cool :-)
Enjoy!
-Mike.