I've had this ring for five months now after trying a number of others and whilst far from perfect it's the best I've experienced.
There are some issues with accurate recording of sleep time and the annoying suggestions that I have taken naps every time I sat down for a while but these can be corrected manually.
Workouts are seldom detected by the ring.
But other measurements are accurate, including steps, heartbeat, blood oxygen, stages of sleep and stress levels.
On power saving mode, the battery autonomy is reasonable, about 3 days.
I've found customer support very responsive and helpful via the chat.