Purchased for use with CAD applications and to alleviate wrist discomfort. It has good ergonomics and materials, and the buttons are silent. It connected easily with Bluetooth. The size is great for my medium-sized hand and overall I don't think it will be a problem because the fastest way to operate it is with the fingers, without gripping it with the palm.

The mouse is heavy in its movement compared to conventional mice, possibly due to the contact surfaces on the bottom not helping. As a result, it moves with some difficulty - I don't have experience with other vertical mice. Using it on a hard and somewhat rough surface improves things. If someone is used to lifting the mouse to cover the movement across the entire screen, this mouse will not be convenient as it does not have grips to lift it. The DPI switch helps easily find the movement speed that suits you. However, the precision in movement is not the same as a horizontal mouse - I don't know if it requires experience in usage.

The great advantage of this mouse is the 2 additional programmable buttons that can be set through its driver. So, you can assign the scroll wheel click to one button and save your hand to a great extent... BUT. The driver seems to have a bug. In my system at least (win10 pro), when running a program that requires administrative rights, the buttons stop working apart from that program. Uninstalling and reinstalling solves the issue, but only until the computer is restarted. Of course, the company did not respond to my email.

--- EDIT 23/1/24 ---
In WIN11, the driver works correctly so far.

--- EDIT 6/6/24 ---
The scroll wheel is gone... After 5 months of use, I will add that it is not very accurate for CAD design and it is also quite tiring for the hand - not for the wrist like other mice. So, I think it is preferable to use a more conventional mouse with programmable buttons for the middle click

Purchase 4/9/23

Positive:
1) Quality construction
2) Silent click
3) Nice design and comfortable in movements
4) Can be connected via USB (wireless) or Bluetooth
5) Convenient side buttons
6) 1 battery now has been here for 3 months (almost) and the response is the same as the first day (8 hours of daily use)

Negative:
1) Small mouse, my hands are thin with size 8 (Medium) in gloves for example, and my fingers exceed the mouse, I have to hold it a little further back with my hand (and not grip it) in order to be able to use it, so this mouse is for those with hands of size 6-7. Personally, it doesn't bother me but I would have liked it a little bigger, I didn't notice in the title that it is mini when I bought it.

It took me about 2 weeks to get used to it, but once you get used to it, it's a different experience, very comfortable for the hand.
In short, I don't regret it as a purchase, it turned out well. I hope it lasts.

EDIT 11/7/24:
The scroll wheel started not working properly within 1 year (very bad), it goes up and down randomly, it would have been useless but I fixed it and it continues to work normally. (I opened the mouse and at the point of the scroll wheel, besides cleaning, I put tape so that it fits better on the sensor and now it works normally again) let's see how long it will last.