I've recently gone R2R with the P6 Pro and it's funny how we only fully notice the glare of Delta Sigma DACs when it's removed.AKM dacs can have a shine to its treble too. Just it'll be step less than the ESS. You just need to find a company that knows how to implement the ESS or AKM to reduce this feeling.
R2r works.......though they sound so boring unfortunately. Wont slam as hard, and will not as be incisive sounding for the imaging dynamics. But you definitely won't have that shiny treble sensitivity.
That glare has a way of masquerading itself as detail and does make notes feel more incisive, but there's an associated ringing effect that fatigues. I'm not dissuading anyone from Delta Sigma DACs, AKM DACs in particular are wonderful for the way they portray wide soundstages with inky black backgrounds. Implementation is key.
The Quattros are great because their smoothness effectively negates a lot of that treble fatigue. I agree they love power, as you'd expect with four DDs.