So, I bought my Sundara this year and assume it's the revised model (should be). I don't hear this grain you speak of personally. I have mild/light tinnitus, so maybe if it's very, very subtle I would miss it? Also, the peaks seem to be mostly gone on this revision. I currently am only using a bass shelf on EQ because I prefer more bass than the stock rolloff. Everything else sounds solid to me, though maybe I'm less discerning than some.
I've included a measurement by oratory1990, which is nearly identical to Resolve's measurement in his latest review. This actually sounds great to me, and trying the EQ oratory has for the latest Sundara revision sounds a bit oversharpened to me. It's possible I prefer slightly less treble than Harman, or there are some minor discrepancies here.
@Eddie C Those pads look extremely comfortable! For $22 those look very high quality, thanks for the update on that.