I got one a few weeks ago. It is interesting. I am still in the longer calibration period, so the coaching functionality is not yet available. Although, that is not why I got the Whoop.
I have problems sleeping and wanted something that could track it better than my Garmin Fenix 5X. The Garmin has been increasingly providing what I think is inaccurate data. For example, reporting total overnight sleep time of about an hour. I sleep poorly, but not that poorly.
After a few months, I will decide if I am getting anything useful. If not, I will cancel the service and move on.