I have the watch for a few hours. First impressions are very good, the screen is very bright with nice colors, the speed is also very good. I believe its functions will cover most needs, I would have liked the speaker to be a little louder but it's a watch. The microphone, from what I have tested, is not the best but it does its job. I will try the eSim connectivity as soon as I get my hands on the QR Code, otherwise it is a very decent watch even if the battery needs to be charged every night

Everything is working, and I'm waiting for the provider to give me the QR code to connect to LTE. If it works, it will be perfect.
Despite many settings for every taste.
I would say it's perfect if the battery lasted longer.
I connected the e-sim to the provider and it works perfectly!

It's super the watch, a little better battery life I would prefer but we can't have it all, everything else is perfect.

I got the LTE version so that I can use the watch independently with multisim. Although it is quite expensive, I took the step and bought it in installments. The first 3 days everything seemed excellent. As soon as I inserted the esim and started using it without the phone, the problems started...
Intense heat on my wrist and an overheating message, followed by immediate flight mode. Every time I used the esim, it did the same thing. I returned it and they sent me a new one. As soon as I inserted the esim in the new one, the exact same issues occurred. I spoke with Samsung and they claim ignorance. I spoke with the eshop where I bought it and they told me they can send me another one, but it's better to take it for service to see what's going on. 500 euros for a watch that you can't use the LTE on and I'm struggling because Samsung releases watches with such a flaw.
In discussions on the Samsung community forum, they mention the exact same problem since August, abroad. Other than that, Samsung knows nothing! I don't know what to say. I will probably return it. It's a shame because it looks like a nice watch...
Anyone who wants to buy it, please don't get the LTE version.

Update 4/3/2021. After 5 months of trouble and 2 visits to the service, I can say that I have what I paid for. It doesn't overheat, I have full autonomy compared to the phone, music, calls, and top applications with esim from Cosmote. You can do whatever you want. Obviously, with the recent software update, the watch was fixed. The blood pressure measurement and the electrocardiogram are a particular advantage... I am very satisfied and I don't regret it at all.
4 stars for the trouble and the high price.

Stay away from this watch if you have an iPhone, as it is not compatible with any notifications (SMS, Viber, WhatsApp) and requires a special way to answer calls as the relevant touch icon does not work. Additionally, the oximeter and electrocardiogram applications are not yet available in Greece. The company claims that some of these features/applications will work with a future upgrade. However, their official website mentions compatibility with iOS as well as the oximeter application. In other words, complete deception. Also, its battery does not last more than 1 to 1.5 days