Its a amazing to see guitarist talking about %.
As a pro photographer, 1% different (RGB vaule) in color either makes it or break it when publishing. That's why I invest in $2000+ LCD screen to get high color spectrum for editing.
For Helix, even it s small % increase over HD500 (which I own), it means less tweaking, less editing, and more refinement. I like the Hd 500, but there is a different even just listening to those demo vids. Overall voicing is much better when u direct out to recording.... maybe it just me.