I have one test on Ancestry.
For 'parent 1' (my father) it lists 4 common surnames- his grandmother's maiden name, his mother's maiden name, Smith & Allen. Well, he does have Smith ancestry far, far back as well as Smiths who married into family over the years but ALLEN? The only 'Allen' I can think of was the first name of great-grandfather's cousin! The next most common surnames are his great-great-grandmother's surname, Andrews, Ellis, Miller, Adams, Anderson. None of those surnames I mentioned fit anywhere into his family.
The Origins bit isn't that far off. On his side I have 23,458 matches.
For 'parent 2' (obviously my mother) only one of the common surnames is a mystery.
On this side I have 18,213 matches but the Origins bit is off to say the least. I should start by saying mother's maternal side is German & her paternal side is 1/2 German and 1/2 English. So roughly 3/4 German & 1/4 English for my mother? No. 4% Germanic Europe, 3% France (part of family lived on German-French border), 37% England & Northwestern Europe, 6% Sweden & Denmark.
Good thing I'm not going to these estimates to trace my family tree!