How much of an age gap would you say is too much between an older man and very young woman?

Say a 27 year old man is dating a 19 year old woman for example.
5 years apart
10 years apart
15 years apart.
As along as both are legal and consent adults, age gap shouldn't matter much.
Other
Select gender and age to cast your vote:
How much of an age gap would you say is too much between an older man and very young woman?
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