The sound became cleaner and higher quality, but the volume remained at the same levels (tested on a desktop with B&O sound card)

Although it is good in everything else, the headphone makes it terrible for some reason. However, I recommend it only if you don't put the microphone on top

A particularly good sound card with good sound quality and useful software. The SBX and virtual surround are nice (although I prefer Dolby Atmos and DTS:X for headphones).

Excellent product without competition in its category.
Very good for music, games, and movies that I tried. Upgrades the sound from my laptop, mobile, and consoles in terms of clarity and quality.

It is not a coincidence that on the website of the most well-known global chain of stores, you will see that it has a very high rating from users, as well as on well-known review sites related to sound, and in video reviews from well-known reviewers on YouTube. Don't just look at the ratings they have here to judge a product before buying it, but also take a look at the worldwide web, there is a lot of information.

I agree that it should be more affordable, but in its category and for what it offers, it has no competition, and if it did, it would definitely be more economical, that's how the market works unfortunately... But still, the price of 50 euros is not terribly high for a portable branded gaming sound card that has all these connections.

The sound quality that this pocket DAC (small sound card) produces is very good for its size, and the volume is sufficient to deafen you, clear, crystal, without distortions even at maximum volume.

You connect it to your mobile via USB-C, download its app (Sound Blaster Command) from the Play Store, and customize its sound exactly as you want with its equalizer. If you increase the preamp to +9, it will deafen you without distorting the sound even at maximum volume. The card stores all the options you have set from the app and remembers them wherever you connect it. Just press the central button with the light, and as soon as it lights up, it plays exactly with the settings you have set, loud, clear, and high-quality. The first time I connected it to the app, it performed a firmware update that took quite a while. Of course, you can do the same via a computer with its software.

It works flawlessly with anything that has a digital optical Toslink audio connection, such as a TV or a PS3, which I tried, and all the saved sound parameters work properly. The packaging includes a one-meter optical Toslink cable.

It works via USB on mobiles, tablets, laptops, desktops, and consoles like PS4, PS5, and Switch, with microphone support. The packaging includes a USB-C to USB-A adapter (regular).

It is plug and play, it works properly even on Windows 7, which does not support the software, with the parameters you have saved from the last time.

You can adjust all the functions remotely via Bluetooth from your mobile at any time.

Also, it is very good and convenient that you can adjust the volume of the sound and the microphone directly from the device using a wheel. Useful, for example, for those who have studio headphones without a volume controller, which is the case for most of them.

Check out other reviews from abroad and decide for yourselves.

EDIT
I bought it mainly for the hands-free compatible input so that I can communicate better through Skype and webex.
Of course, also for music. Or so I thought...

On PC:
Problematic software.
Although the specifications state playback at PCM 24-bit, 96.0 kHz and Mic-in: 24-bit, 96.0 kHz, it only goes up to 16/48.
Transparency and stereo image are mediocre.
The on-board sound card of my old Asrock Z97 Extreme with Realtek ALC1150, in terms of sound quality, is much much better, with much lower noise, neutral detailed sound, and really good stereo image even at 16/44.1.

Also, while the microphone of the hands-free sounds perfect during monitoring, it sounds muffled during tests on Skype and webex, despite the settings I made.

CORRECTION ATTENTION!
While the microphone sounds bad during the Skype and Webex tests, it sounds very good during actual calls, according to what my conversation partners told me. I will come back to this issue.

I also connected it to my LG V40.
The application connects via Bluetooth to the G3. With the settings, you can't do much. The equalizer, in fact, does nothing.
Listening to the same songs in an A-B test, even the standard DAC of the mobile phone sounds considerably better than the G3. Not to mention the Sabre's hifi DAC...

In conclusion:
You only gain volume. And maybe for gamers, you will hear the footsteps of opponents more easily thanks to the special setting.
Fortunately, the hands-free probably work well, but overall, for the money it costs, it should be much better.