AKM chips seem to be more "Relaxed" then some of the ESS Chips
No, they are very similar in terms of native performance. However, maybe these reviews were in regards to specific products using such chips.
As for the Wadia, looks pretty good, the dynamic range spec is pretty poor for the price though ($100 DACs are >110dB), but I doubt it’s an audible difference, seeing as how even 96dB is better than most rooms allow.

