Password vault software

How secure are "password vault" products like Faena MyID? I'm not
talking
about what they claim about the length of key they use, but how
trustworthy
the supplier/developer is. Or, perhaps I should be asking how much
trust I
have to place on the supplier/developer. For example, what would keep
an unscrupulous supplier/developer from embedding a little piece of
code
to send all my passwords to him?

TIA

Ed



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