Purchased for €28, I have been using them daily in the car and on the bike for two weeks, mainly with internet radio. Good battery life, around 25 hours as advertised by Sony. The sound is fine for headphones around €30, balanced bass sound without clogging your ears; there is also an app that you can play with settings, but I haven't bothered. Large buttons, no need to search for them to answer. The microphone is very good, no interruptions, does not distort; a big plus is that through the app you can mute the sound for low battery, which in many models starts the annoying beeps at 20%.
Negatives: there was no USB cable in the package (tragic for Sony), only ear tips. Absence of a magnet (I was caught off guard here, I saw in the comments after the purchase that it doesn't have a magnet), this is unacceptable especially on a bike, I had to tie them in a knot when not in use, that's why I only gave 2 stars. Now, as for the construction, while the back part that rests on the neck is wide and made of quality material, the front wires that lead to the ears are very thin and the headphones are made of cheap plastic; it’s as if Sony made the back cable and the controls, then handed them over to Jumbo to make the wires and the in-ear headphones... tragic construction, it won't last over time, stay away.

I decided not to throw away 70-80€ for headphones that I don't know how long they will last and what performance they will have, but also not to resort to a cheap temporary Chinese solution. At 30€, the SONY headphones seemed like a good compromise. But they did not prove to be particularly worthy of their name and price.

The sound is quite good, above average, but rather shallow, without satisfactory bass. Their size is small so that they can be held in your ear and not bother you if you want to wear them while lying on your side. The battery life is excellent, and it notifies you of its level every time you open them, particularly useful for me as I use them for walking. And the length of their cable is such that you can easily and comfortably wear them with all your clothes, without them hanging annoyingly low if you take them out of your ears.

BUT, they have two serious disadvantages:

First, they do NOT have magnets to hold them together. The truth is that their length and weight (with the battery and controls pods) keep them in place while walking, but I don't think they would do the same while jogging.

Second, they do NOT even come with a USB/Micro charging cable! I didn't expect them to come with a charger, but at this price they could easily have the bare essentials.

Unfortunately, a very bad choice..
Although I had read mediocre to bad reviews on other websites in Greece and abroad, I took the risk and bought them.
35€
Average construction quality, but that's not a problem for me.
Let's get serious.
- From the first call, I noticed a noise when they are in operation. What do I mean? You put them in your ears and make a call. Before it starts ringing, there is a noise, like a whistle. Permanent. This noise is not heard (probably covered) when the other person answers, and it is not detected during the call, but seriously, what's going on? In 2023, I feel like I'm talking from a walkie-talkie.
- It disconnects every now and then.
Although the phone shows connected to the headphones, the sound is transferred to the phone's speaker.
- The magnets are just there to say that it has magnets. They don't hold at all. In the first strong movement, they come off. Otherwise, they are neckband for exercise and all.
- The earbuds (the part that goes into the ears) are from those that if you have slightly smaller ears, they will tire you. Personally, even with the smallest rubber tips that come with it, they don't fit well for me.
+ The positive aspect is, of course, the long battery life.
I can see myself throwing them in the trash in a day or two.

I have them for only 4 days. Compared to the previous HUAWEI headphones I had, I will say that they are inferior.
The battery holds up quite well even with demanding use. The application is okay. Not perfect but very good. Because they don't have magnets on the headphones, they slip right and left. I forgive it because I knew they weren't equipped that way.
They charge quickly.

The major negative is that they turn off on their own. Nowhere in the user manual does it mention a way to disable this setting.
Maybe now that I uninstalled the headphones' app, it will be resolved. I imagine that the app was monitoring battery usage and maybe it put them to "sleep" after a certain time. I will come back after observing it for a few days.

Update: Indeed, after uninstalling the app, the headphones no longer turn off on their own.

The recipients of my calls have mentioned that peripheral sounds can be heard, but they are not disruptive to our conversation.

26.10 2nd update
It is impossible for me to hear audio messages from VIBER, specifically. I have searched forums and no workaround has worked.
When I was in a crowded place, the conversation was extremely difficult for the recipient, who could hear all peripheral conversations and noises.

Overall, good headphones for conversations in the car and at home, but below average for outdoor use. Good for movies or music.
The headphones are connected to a Samsung mobile.