The best one could do to compare converters would be to know what part number was used and whether it was held to be better or worse than any other.
Let a marketing department tell us what we like?
The spec sheets are filtered and approved by marketing. On paper the original microtrack had specs as good as the 722. And in practice it was quite noisy. The specs for an a/d are almost meaningless by themselves because a/d's are entirely dependent on the quality of the device implementation, and other implementation decisions, like the power supply.
Listening really is the best way. And the v3 remains a really great device for evaluating them, because it has a decent built in a/d, and it has an excellent line out section that is not routed through the a/d. That doesn't allow direct comparisons of two third party a/d's, but it does allow them to be fairly easily compared to the v3's a/d, with a minimum of compromises.