What I like the most is that AP80 sounds neutral with no tendency to emphasize any frequency. Lows, mids and highs are in good balance making this DAP universal to feed it with any kind of music genre. I would call it a precise source for connecting any further audio equipment like headphones, large power amps, active speakers, etc.
—-marketchangers.wordpress.com

The Hidizs AP80 Pro digital audio player is a compact portable player with a natural sound signature that is powerful and detailed. It can handle many musical styles and is extremely powerful for its size. Pricing is fair and build quality is decent. The screen resolution is clean and the player supports many Hi Res and wireless protocols. Providing a great value package putting it in the league of mid to top tier Daps for a fraction of the price. We recommend this player and feel it will be a great addition for most users out there wanting a compacted versatile DAP.
—-earphonia.com

Honestly, the Hidizs DH80 came as a massive surprise, in a tiny box. More than a good addition to the AP80 Pro-X, this is the PERFECT addition to the DAP, for anyone who needs a tiny power-house, at an affordable price.
Even as a stand-alone, I found the DH80 to be quite potent, and I had a really good time using the DAC with my Macbook – even if for that use, I’d really suggest you to get the Hidizs DH80.
—--headfonia.com

On the go, it’s a pleasant device to use, and the small size is great for commuters like me. The lightweight body makes, combined with the elongated design, makes it easy to fit in a pocket. And, if the default cable doesn’t ply correctly, once replaced by LT02, the combo Hidizs S9 Pro + iPhone fitted right in my jeans pocket.

—headfonia.com

Moreover, S8 supports iOS, MacOS, Windows and Android. No drivers needed. All of the operating systems would recognize S8 as an audio output device and would allow to use all of its features. I have personally tried to use it with Windows 10 laptop and Android 8 smartphone. In both cases it was natively recognized by OS and allowed up to 32bit|384kHz PCM stream. The only note from Hidizs is to connect headphones to S8 prior to connecting it to the source device. Otherwise, S8 might not be recognized correctly.

—-marketchangers.wordpress.com

The S9 has excellent output power and can drive virtually anything under 150ohm very, very nicely.  The low end of the S9 feels more vivid and velvet-like, feels lively, forward, and with a hint of a natural tonality that is less prone to sound sterile or clinical. 

—headfonics.com