It rocks! Exactly what I needed, truly!!!
Easy, straightforward, can remember up to 3 connected devices, silent and lightweight!
Not only do I recommend it, but I suggest it without hesitation.
The only negative someone might mention is that it takes a minute to connect.

If your laptop keyboard is broken and you can't find a replacement or it's expensive, this keyboard is the best option. (it's almost flat, thin, light; I put it back on the old keyboard with bluetak and it's just fine)

It has a very good typing feel, but I don't recommend it unless someone wants something very thin and light.

With Bluetooth 4.2, I had disconnections; maybe it has nothing to do with the version, with a USB Bluetooth 5 it's fine.

If it's inactive for a long time (I don't know exactly how long), it takes 2-3 seconds to start up, but it hasn't bothered me at all; it happens, for example, when I walk away from the laptop.

*I use it on Ubuntu 22.04 without any problems
*the battery lasted 2 years, but they are cheap to replace

It is very good. It is so and so for developers since you have to look at the F keys for debugging as there are no gaps. Also, it doesn't have a backlight at night :(

Excellent quality, quite compact - therefore not suitable for prolonged use, the Bluetooth connection is not very stable, but Ok, Microsoft support software is average.

Positive:
- The new Microsoft membrane in the designer series is very good compared to the attempts it made in the past to reduce the distance, e.g. the desktop wireless 900.
- The keyboard is a gem in the office.
- They have indeed made many improvements in the distance between the keys and their feel (Microsoft had issues when it tried to reduce the distance on its keyboards).
- It is a laptop-style keyboard with low-profile keys (once you get used to them, you won't go back to keys with a larger distance).
- It can be connected to 3 devices.

Negative:
- Its connection is not the best, if you try to type after a while, it lags a bit, then it's fine.
- It is not as comfortable as a ThinkPad keyboard (the new ones with 1.5mm key travel) where even if you are unfamiliar with keyboards, you can type as if you have been doing it for years.
- I suppose a typist wouldn't love it, and it might be better to go for the sculp series.
- I think it lacks height in the back.
- It definitely needs a wrist rest, either separately or included in the packaging.
- It only works with Bluetooth.
- I understand that it is a new technology with membranes and that the people involved in its development need to be paid, which is why you pay extra for it, but I believe that even so, it is quite expensive for a small keyboard.

In the end, I returned it after 5 days of use because my wrists were hurting.