No I'm not kidding, sadly. I listen to Japanese music a hell lot more English music and I dislike how "zuto" ("always" in Japanese) occasionally sounds like "juto" or "suto", which doesn't mean "zuto" at all.
The most common sibilance problem with the Westone 3's is sometimes, if not most of the time "s" sounds like "z" and vice versa. But of course, for Japanese music only.
Like you although I ONLY listens to Japanese music. I starting to notice a pattern here. Japanese music lover seems to prefer cans with very good high or treble oriented signature. And the next thing would be details details and more details. And certainly no bass heavy cans.
If Westone 3 is a no no for Japanese Music lover, Audio technica's new triple driver IEM ATH-CK100 might be our last chance... it has two driver for high/mids and one for low.(I'm sure it's treble oriented lolx)
So ZephyrSapphire, care to take the plunge