The P8 by YINJW look very similar to KZ's ZST model, especially in color and materials, but the shape is quite different. These earphones have their unique sound signature, thanks to the triple-driver setup, but that sound isn't necessarily good. Sure, the separation of detail and sense of direction is quite impressive, but these earphones are overly bassy in nature, darkish and tonally inaccurate. Some emphasized frequencies (probably those around 2kHz) managed to cause me some fatigue.
Truthfully, I expected more from a triple-driver setup, considering their price. There are far better single-driver options.
The volume buttons work on Android devices. I don't have an iPhone for compatibility check.
Comfort & Fit
Fitting them properly takes some effort. When worn too loosly, the sound is mellow and lacks impact, but when worn too firmly, the sound gets overblown with mid-bass. So, again, the problem isn't really discomfort, it's fitting them exactly as intended.
Lows / Bass
The mid-bass is very prominent and tend to be overblown, especially when percussions are being played. I find the lows to leak into the mids quite often and actually managed to cause me slight headache after a while.
Mids / Vocals
The mids are very warm, but are also inflated and sound a bit tubby. The mid-bass is very prominent which impacts vocals greatly. The mids are on the darker side, they are quite detailed but not tonally accurate, thus don't sound natural. Female vocals sound too bassy. I find certain frequencies to be too pronounced, while others being underemphasized, which creates a generally uncomfortable dynamic range.
That being said, the instrument separation is surprisingly good.
Highs / Treble
Very detailed and the separation of subtle sounds and microdetail is highly impressive. However, the highs are tonally inaccurate and lack much needed brightness and brilliance. The separation of instruments can be impressive but also disorienting when not used to.