The 4 stars are for the insane price, regardless of the quality. It is the first Bluetooth headset that, in many sound scales, can compete with and surpass the wired set I have, consisting of the Sony MDR-Z7 headphones and the Sony PHA-3 headphone amplifier, with a total value of 1500 euros! As a demanding user of audio files who listens to very demanding music, rich in the entire spectrum of sounds, I am initially satisfied with the clarity and fidelity. I hear sounds with the same naturalness that the top Sony set provides, while also highlighting the finer sounds. The separation of instruments in the very difficult music I listen to (folk, rock, light, Greek music from the 60s, 70s, and 80s) is noticeably better than the other Bluetooth headphones I had (most recently the Sony WH-1000XM3, WF-1000XM3). I am testing them as I write this review, listening to the songs I just heard yesterday, and I am very satisfied with how they sound! And they haven't even "settled" yet, a process that takes 1-2 months. Bass, midrange, treble, vocals, guitars, drums, everything is reproduced faithfully.
The transition from one Apple device to another is much easier compared to the AirPods Pro.
Conclusion: It's a shame that Apple set such a high price for them and doesn't give more people, users of the Apple ecosystem, the opportunity to enjoy them. However, anyone who is willing to invest in them will ultimately be satisfied. I decided to buy them after carefully reading reviews that all emphasized their exceptional sound. For me, that was the primary concern.
After two weeks of use, in 7/10 of the songs, I discover small or large details, despite the countless times I have listened to them so far. For now, the treble is somewhat emphasized, but with "settling," they may improve. However, after 1-1.5 hours of listening, I feel much better, having listened to my favorite music in very good quality compared to the Sony WH-1000XM3, MDR-1ABT, MDR-1000XM1 that I had until recently. These headphones were clear, but they "made up" the naturalness of the recording, compared to the AirPods Max, which highlight the natural sound. Also, the problem with moisture formation outdoors at temperatures of 10-18 degrees in winter and early spring is real, and after use, they need to be cleaned under the earpads.
Update 7/12/2022: Unfortunately, they have a problem with noise cancellation, despite the minimal and careful use I have given them, and Apple refuses to replace them within the 2-year period, as they were purchased from a store, which is unacceptable. Unfortunately, the store is not responding, it is out of operation, and I have contacted the consumer advocate. It is unacceptable for headphones of this level and value to hear a whirlwind when noise cancellation is activated. Let's hope it's a software problem and will be fixed in a future upgrade. Unfortunately, they didn't even know how to tell me that...