You are asking questions about the future that nobody can answer.

There are no missing notifications with the Global EU ROM.

I have no idea how to answer about your battery and notification question – the premise does not make sense.

Hyper OS 2 is a different skin than One UI 7 or the Pixel skin. It feels like a super fast stock Android experience, much faster and responsive that on a flagship Samsung or Pixel device. If you can use any Android skin like Sony, Pixel, or Samsung then you will find Hyper OS 2 very intuitive and have no problem using it.

If you think that a manufacturer is going to try to cripple your device with future updates – I’ll refer that question to the “tinfoil on your head” forum.

With the minimal and minor OS 2 updates received since release, there has been no slow down. Nobody can predict the future on a new device with a new processor and new software. The only manufacturer causing real issues with their updates lately has been Samsung with the failed and buggy One UI 7 launch – it is really a mess and one of the reasons I switched to Xiaomi for a premium software experience.

There is no way to predict the physical longevity of a device, but the X15U appears as well made as any flagship device available right now. There are people that always have issues with any phone from any manufacture; from green lines on displays to buttons falling out to batteries swelling.

Camera island – I am not sure how you “assess” it as fragile. How can anyone predict how you will treat your phone? I never use screen protectors and never get scratches on any of my phones (flagship Google and Samsung), other people swear by screen protectors. You can always use the Photography Kit case and install a clear filter to protect the camera assembly is you are worried about it.

Point and shot works great. Especially the Leica Fast Shot mode – probably the best of any camera you can buy. If you are a Leica user the entire interface with be familiar to you.

If you search YouTube you can find photographers that review the X15U from a photography perspective that go through all the camera settings. These same multiple reviews all chime in on their feelings about saturation or natural color reproduction – if you can find two YouTubers that agree on anything photography related – good luck.

Flossy Carter usually does good reviews on all the Hyper OS 2 features. If you search for Hyper OS 2 on YouTube, there are multiple videos to review.

Call quality is absolutely fine. Speakers are also great – you have to set it to Xiaomi sound, if you use Dolby it is sounds below average.

Samsung gives you the new and “upgraded” S – pen (that is a joke – the S23U s pen is better with BT). Samsung gives you longer software and support, but I imagine you will have moved on after 4-6 years, so that is irrelevant. Xiaomi give you a better camera system with Photography Kit – a real game changer. I love playing around with Good Lock modules, so you will not get that insane level of customization with Xiaomi.

I keep my Samsung as a backup device and rock my Xiaomi as my primary. But to each his own. We all have different criteria – only you can decide what is important to you.