Just unboxed these and popped them into my ears with no burn-in, using the default tuning (which includes the gold nozzle, not blue as indicated in the manual). Wow, these are fantastic! Using the pre-installed silicone tips, the seal is terrific, among the best I've experienced. These ar some good eartips. I'm sure there may be some changes with some burn in, but even if not, I'm more than satisfied. Mid-range and treble detail is abundant but never in an aggressive or harsh way. Treble is well-defined and well-extended, with no sibilance. Bass quality is top-notch, quantity is about neutral with the reference filters. I'll likely end up going to red for the ULF as I'm a bit of a sub-basshead. The vocals are so immediate and defined its almost uncanny. Yet the soundstage is wide and expansive and instrument separation is terrific. This is an IEM that is both highly detailed and analytical, yet very musical at the same time.
A couple of non-sound-related comments. The boxing is the best I've seen. I love how you see "open here" when you first unwrap them, then as you proceed through each step you see a direction for what to do next. Very clever and well though out. The cable does have some microphonics, but not too bad. Cicnching the cable tighter to the chin helps a lot. I may look into a replacement cable that is less microphonic although I could be OK with this cable, as I don't intend these for active use.
Looking forward to trying the red sub-bass filter after some more burn in time. Its likely the only change I'll try as the rest of the frequency spectrum sounds spot-on to me as is. Just playing music through them at a moderately loud volume to put some hours on them. I've made a couple other IEM purchases lately that I really like, but I can see these getting nearly all my ear time. They remind me a bit of my Sennheiser HD 600. Timber and tonality are similarly accurate and both lay out a lot of details but let you relax and enjoy the music at the same time.