I haven't read the previous 60 pages, and I'm not sure what the incoherent drama is about, but the Sundara is the best sounding headphone I've ever heard. I returned the LCD2C and sold my E-MU Teak, HE4XX (too bright, sounded nothing like the Sundara), modded M1060 (which I kept for 8 months because it was amazing), and K10UA. My headphone collection has been reduced to just the NFB-11.28->Sundara for home and the DFR->HD6XX in the office.
To my ears, the Sundara is neither warm nor cold but straight neutral (incredible timbre, very rare for planars) with very low distortion throughout the FR (typical of good planars), no ortho wall, incredible transient response, resolve, imaging, and is the first planar headphone I've heard with above average sound stage that has depth and center in addition to width. I literally cannot find fault with its sound.
I cannot overstate how resolving the Sundara is. I hear subtle nuances in breaths, strings, plucks, and in the background that I never hear on any of the above mentioned headphones, sans the K10UA. Yet the detail resolve sounds very naturally retrieved, rather than due to some artificially high treble elevation.
Sundara was a couple of firsts for me. Before the Sundara, I thought my sensitivity to treble meant I would forever favor warm-tilted headphones. The Sundara, on balance, is the most treble forward headphone I've loved because the treble always remains smooth and never becomes harsh, bitey, or sibilant. This experience has made me wonder if I should give the HD600 another try in dethroning my HD6XX. Also, listening to the Sundara was my first experience in actually hearing what "veiled" sounds like first-hand, aside from reading about it, as the LCD2C, the M1060, and the HD6XX sounded veiled in comparison.
The only gripe I have about the Sundara is the same gripe I have for all HIFIMAN headphones I've tried, which is that the 55mm round ear cavity on HIFIMAN ear pads is just too small for my ears. I can, with a higher level of carefulness than I'd like to exert, wear them comfortably, but I'm waiting on a pair of Brainwavz XL hybrid pads to try. To the Sundara's credit, the default pads appear to be a more premium revision of their Focus pads, with the velor part replaced with a perforated cloth mesh.