I still do find universal IEMs to be superior to CIEMs in terms of comfort. Fit is another thing when it comes to keeping a seal in extreme cases. Then gain for the most part I don't have such issues on the Sui or FX850s.
Well it could depend on how the silver-gold cable is manufactured as well. I am using Tralucent older gold cable which sounds quite different than the new version. I like how it sounds on the SE5. It pretty much takes the SE5s approach on music and makes it more natural, with more depth to the sound staging. Lusher mid range, with more textured bass. Treble is smoother.
My point is I don't totally buy into that. In general yes humans can't hear outside of a certain threshold but that doesn't mean that applies to everyone. Just as some are more intelligent, have better vision, etc the same applies to hearing.
I think he means it has one of the widest soundstages but the 1Plus2 still bests it in that area. The 1Plus2 most definitly wins out still in clarity. The 850s mids are a bit more forward with the 1Plus2 having a cleaner sound across the entire spectrum.