After a first look, the following observations:
1. It fits very well on the phone.
2. It has a difficulty in coming out of the phone case, but with a little caution, it comes out.
3. Very good build quality and overall feel.
4. The only negative is that it doesn't fasten from the front, so in case of a fall, the front part doesn't open and cause damage.
In the end, for the money I paid now in 2021, it is a very good purchase

3 stars because my phone broke while I was wearing it... There is no magnet to securely close the cover, so it opened during the fall and landed face down... Luckily, only the glass cracked a bit in the bottom corner and didn't affect the screen.

I would give it 5 stars, but it fits annoyingly perfectly on the phone and it's difficult to remove if you don't want to throw your phone across the street. Expected, of course, because it's the original. The rest is simply perfect. The quality and design, which flashes in notifications, combined with the full protection and good quality of the materials, which provide excellent protection, make this case worth its money 100%.

+It has the nicest design I have found in a book case.
+It's nice that when you close it or receive a call, the outline starts flashing.
+Relatively cheap for an authentic Samsung, usually they are much more expensive.

-Once you put it on your phone, it stays there forever: P I tried to remove it once and almost threw the phone across.
-You can't put a metro card inside because, from what I understand, it interferes with the NFC function that the phone uses to interact with the case, so it won't turn on:(
-I hope it holds up. I can't have a complete and informed opinion on its durability since I have had it for a few weeks.

~EDIT 4-6-18~
So far, it has taken a few tumbles and although nothing happened, in all cases the case opened, causing the phone to fall face down. This worries me because I don't know how certain I can be that the next time the glass won't break. It also has some visible marks from the falls.

Edit 10.8.18
The phone fell and made a huge dent.

The primary purpose of the case is to protect the mobile phone, especially when it is made by the company that produces mobile phones. The case DOES NOT protect the mobile phone. It opens very easily with the slightest touch. It is made of something between rubber and plastic. The effect on the outline is activated by a chip that takes advantage of the mobile phone's NFC capability. Personally, I am not impressed, especially considering that it has a flaw if you turn off the mobile phone outside the network.

The build quality impresses you, the phone buttons click very well but do not come out easily enough, after answering a call you can close the case and continue the conversation normally without the cover bothering you or smudging the screen of the mobile! If it had a magnetic lock, it would easily earn 5 stars.

+ Beautiful
+ It hugs and buttons very well on the phone with hard plastic back and sides.
+ The orange outline (which is an extension of the inner surface) lights up when the phone screen lights up :)
+ When you open the cover, the screen opens too, without needing to swipe your finger on the screen :)
+ When you close the cover, the screen immediately turns off and the outline lights up momentarily :)

- It doesn't close securely, if it falls, the cover may open and hit the screen below :(
- Expensive