There are too many downsides and few upsides.
If you’ve got a genetic condition that’s going to effect your later life, sure, go ahead and get that tested, but I doubt a £100 generic test is going to reveal much to you without the surrounding counselling and medical advice with which to deal with and do anything about it.
I read somewhere that go back just 8 or 9 generations and the amount of pairs of people involved in you family tree is already in the thousands, and that’s just the direct forebears. There’s potentially an issue that will get you regardless, and TBH, that’s just chance. welcome to humanity