I am looking to buy Ultrahuman ring , can one share feedback for the same ?

I generally tell people to check built-in error with all these wearables. For example - Apple Watch usually show higher calories burn against more sophisticated laboratory setups.

I'm using it for the past year plus. It's good if you don't have life altering expectations from it. Does its job very well, but the metrics read are not absolute; but an indicator to help you with decisions.