I don't like
Devin, which is a boy name to me and rhymes with
Kevin (DEV-in). Sounds diabolical.
I think
Devon (DEV-un, roughly - does not sound exactly like
Devin but rhymes with ) isn't a variant of
Devin at all, and is a trendy-ish place name for girls, sort of like
London. I don't like it on boys. I think it's rather nice for girls.
I've met one young woman named
Devon and no others. Some newish unisex names make a homely person seem more so IMO - like
London and
Rowan and
Emerson - and seem to depend on the bearer being young, femmey, and pretty, to "work." But
Devon doesn't have that effect, to me. I can picture
Devon seeming dignified and modest and non-lame on a woman whose overall impression was of severity, as well as it suited the young
Devon I met who seemed young and happy.