I did one of the early rounds of it, partly because I was curious (in specific: family heritage that made the BRCA genes relevant, but also no particular family history of breast cancer). I did it with the idea that if it turned up anything relevant, then I would go to my doctor and check on it further.

(And a couple of other things that turned up are not make or break deals, but knowing about them turned out to be helpful in approaching a couple of chronic things more sensibly.)