There are no obvious major shortcomings, but there is some incompleteness and underdevelopment or something, there is no such thing as to say - "Wow, cool, everything is done super!" So:
1. Declared autonomy up to 5 days - and yes, if everything is turned off (constant monitoring of heart rate, oxygen in the blood, do not turn on training modes), then, yes - it will last 5 days before switching to the "just watch" mode, BUT if you do not turn it off and use all the functionality - and there are a lot of convenient things - analysis of the level of stress, fatigue, you do not need to enter a password every time when paying for NFC (otherwise, with each payment - a password, but this is not convenient, otherwise - only when you took off your watch or once a day) The charge is enough for a maximum of 3 days, even, probably, for 2.5 days. Upon reaching 20% of the charge - they write to you - "low battery level" and NFC does not turn on. Someone in the reviews wrote that with all the functions enabled, it lasts for 4 days - this is not so.
2. Double tap and wrist movement does not always work - it sometimes pisses me off. At the most necessary moment, when you stand at the checkout before paying - the watch shows character - you have to tap your finger many times. How and why this happens, I did not understand - this was not the case on HONOR band 4.
3. And yes, people have already written that at night the arrows are not visible at all.
4. The nylon strap does not dry out immediately - after a rubber bracelet, this is a little unusual. But this is all solved by buying another strap.
5. The price of 30+ is, of course, a bit high. I bought from the official with a guarantee. But there are no analogues and competitors (only Fossil), so if you want a hybrid watch, you will have to pay.
6. The phone search function is stupid and unusable (the description is in the reviews) - finding a phone using it is extremely difficult. It was simple on the bracelet - you pressed the button - the phone beeps and you find it, and here is the eternal game of "hot-cold". Garmin, if you read - correct, please :).