I’d never heard of Oura before today - the idea of having it in a ring seems genius to me, I hate the idea of wearing a wrist strap as well as my watch.
Also it seems like it’d be easier to keep under a ring properly clean than under a strap (i.e. my wedding ring which has never given me any issues, vs my watch which I have to leave off for a day or so every now and then as I start to get itchy).
I’m quite tempted by Oura, but might see how Whoop 4.0 comes up once the reviews start to roll in.
Another thing Whoop have going for them is the subscription pricing model, as being in the sunlit uplands of post-brexit Britain it’ll cost me a great deal in tax and import fees to import an Oura.