Yes, the Oura ring is a remarkable device and gives some useful, interesting and actionable biorhythm and physiological assessments.
I was an early adopter of the Oura ring, I just counted and I have six of them. I’m also part of the Oura user testing community so I get the betas. For disclosure: I use a Garmin and a Polar Heart Rate Monitor (HRM) for for exercise times, speeds, distances, VO2max, Heart Rate Variability (HRV), etc. The Oura ring for me is primarily for improving sleep.
I think we have to be sober about what we can reasonably expect Oura to deliver given its size, proximity and from taking readings thru the skin of one’s finger. Oura uses infrared, red and green LED sensors to get its readings. I believe the respiratory rate, heart rate, blood oxygen levels, and body temperature measures are surprisingly accurate. I think the heart rate variability (HRV) is a little more “approximate” but still a good indication of sleep HRV, if you don’t need to know precisely. HRV doesn’t measure during the day time other than perhaps providing data for some of the new features.
The Oura algorithms, and each new version of the ring (current V3) have all improved massively helped by a growing community of users (I think I read that there are over a million rings sold) and the incredible user data they have collected. The online Oura Portal is impressive for data analytics and geeks. I think sleep, in all its forms and readings, is quite accurate.
The Oura accelerometer logs your activity and movement. Not its best feature but seems to work ok for indicative data and its amazing to put it into a small ring.
The measures of stress, heart health and resilience are indicative, fun and novel but even clever analytics are limited by the ring placement and sensors.
HRV is important and valuable data but more difficult for the Oura sensors to pick up but it’s useful for indicative sleep HRV without strapping up in bed. I occasionally want a better measure of HRV so I use the Elite HRV App and my Polar (HRM) for this measurement.
As for the new cardio vascular features analysing age-related observations for cardiovascular age, ie VO2max and arterial stiffness and pulse wave velocity (PWV). That sounds wonderful but I have to say, I’m dubious about the Oura ring delivering any level of accuracy in these areas and I’m a little bothered that they feel the need to hype what is already an extraordinary device. I really hope they can deliver accuracy for these new features.
Perhaps Samsung entering the market has them spooked? Samsung are a smart company and they know how to build great technology but I think that Oura’s collected user data is a goldmine that will help them refine the capabilities. I’ll be waiting for Samsung V2 before I change rings.