I have an oura and love it. Absolutely key to figuring out some health issues I was having. So happy with it my wife got one for herself. Wear it 24/7 except during some workouts.

After a year with an oura the biggest takeway is it is not a workout tracker, it is a recovery tracker. It will tell you how your body is recovering from the stress you put in. It does a terrible job tracking any workout I've tried other than rucking and you can't see live data to target a HR zone, only a summary after.

So my current approach is, oura app is my central touch point for all fitness tracking. polar H10 for any target HR workout, kettlebells and rowing in my case. I manually add that workout into oura after I finish based on H10 data. Oura is good enough for rucking for me. When I'm fighting, BJJ, I just use the oura app estimator to track that workout.

This may sound slightly down on oura, it isn't. After a year of training with it I've totally flipped my thinking to what is normal. Knowing your recovery state is far more important than knowing how hard you worked. 

My advice to any curious biohacker is to get one. Without it you have no real information about how your self experiments are affecting you.