I have had an Oura before. The 5 fits better, looks better, and provides even more insight. For me, insight into sleep, stress, and the combination with another app is the most important thing. You get extensive insight into your sleep duration, sleep phase, heart rate, HRV, stress/rest, and calorie consumption (based on activity). There are also other options that only become visible after longer use (such as sleep chronotype).
Activities such as steps, cycling, walking, etc., are automatically detected.
The ring is waterproof, so you can wash your hands, shower, and do the dishes with your ring without worry.
The only downside I experience is that short interruptions during the night are not visible. You do see moments of movement during the night, though. However, it does not detect being awake briefly, which makes you tired in the morning. As a result, my sleep score is higher; I think that is how it is supposed to be. If I get up or stay awake longer, the ring does detect it. Also, if I watch TV in bed, that is sometimes considered light sleep. You can manually adjust your bedtimes (falling asleep and waking up) in the app.