I had an Alpine car stereo before, so I bought another one of the same brand.
Cons: The quality of the materials is inferior, the buttons are very "flimsy," and overall it has a "lighter" feel (made in China, like the previous one).
The On-Off button is inexplicably large (fortunately, you can adjust the brightness and it doesn't bother as much at night).
The dial hides the 2 buttons for changing stations to the next or previous one.
It doesn't come with a case for the front panel if you want to remove it and store it somewhere, luckily I have the old case that fits it properly.
The small button for ejecting CDs is hard to find by touch.
Pros: The sound quality is good, but don't expect deep bass and at high volumes, noise starts to appear. I have it with 4 Pioneer speakers plus 2 small NZ ones in the mirror triangle that I had from before.
It connects instantly via Bluetooth with the phone, I haven't tried CDs, it comes with a detailed instruction booklet.
I have the old remote control, which works fine, but it doesn't accept the universal ones from the internet that can be attached to the steering wheel.
Overall, on a scale of 10, I would give it a solid 8 because of the brightness settings, otherwise a 7.

Initially, I had the Pioneer mp80 which performs very well. Recently, I replaced it with the Kenwood 356 and I was really disappointed. So, I replaced the Kenwood with the Alpine 203 and I was even more disappointed. The Pioneer is by far the best in all aspects but also more expensive. Two levels below is the Kenwood which, although powerful, does not perform well in the midrange and overall sounds muddy. The Alpine is simply the worst. It may have slightly clearer vocals than the Kenwood, but overall it lacks depth in the bass and sub and tends to screech in the treble.

It's worth its money. I had an f&u, no comparison with this one. I only have 4 average quality factory speakers and it's like having a sound system, either from the bass they produce that left me speechless, or from the clear sound they have.

Amazing sound from the Bluetooth during conversations. Very high quality and noticeable upgrade of the sound without having to change the speakers.

I entered a Nissan Micra 2000, with the prospect of transferring to another car in the future. No comparison to the previous one. Even with the original speakers, you can see a difference.
The Bluetooth is very good: once you set it up, it connects directly to your device when the audio system starts without doing anything. You can change songs, pause, etc. from your YouTube/Spotify playlist using the buttons.
The calls are of very good quality, and the Alpine reads the contacts of your mobile, so you can make calls directly through it (unfortunately, it does not display Greek characters!)
FM, CD are fine, I haven't tried USB.

Pay attention to the Bluetooth connection, which may seem a bit strange, but if you understand it, it's a piece of cake. I'm writing this here because at first, I had trouble figuring it out from the manual. The audio system can store/pair up to 2 Bluetooth devices. And to set which one the sound will come from, after pairing, you need to find the AUDIO DEVICE option in the Bluetooth menu, where you choose one of the two. If you want to connect a different device and both slots for Bluetooth devices are filled, you need to delete the Bluetooth settings and then pair the new device! To do this, you put the audio system to sleep and then go to SETUP->BLUETOOTH->BT INITIAL (an option that only appears in sleep mode). After that, you can pair up to 2 new devices again.

It does everything. From CD, Bluetooth with 2 separate devices, AUX, USB, and of course radio. It comfortably makes calls with the included microphone, with the ability to reject/answer calls wirelessly. RGB lighting, detachable faceplate, and many sound settings such as bass engine fader balance LPF HPF, etc. Separate color settings for the buttons and the screen. I only have one complaint. The fact that it does NOT have a pouch or even a case!!! It costs so much money, Alpine, come on :)! The volume goes up to 35, although from 30 onwards, distortion starts (there is also a YouTube video that proves it with a multimeter on that specific source). Remote control capability from the steering wheel, although this depends on the model. You may need an interface for the steering wheel controls to work, with a cost that may not be worth it. I should note that it does NOT recognize Greek characters. Only English. Titles, headers, notifications, etc. In case someone wants a detailed display of what they are listening to. Everything is in English, otherwise, it shows nothing. The best source for me.