SmartErase is one of two things: a quick or a full erase
A quick erase will destroy the Table of Contents, which results in no drive being able to recognize the disc at all, and you will not even get a chance to look at the data. The data itself is not destroyed, so it could be retrieved by a data retrieval company with specialized equipment.
A full erase destroys everything on the disc. Presumably a data retrieval company will not be able to retrieve the data, although I'm not aware of any tests proving one way or the other if this is actually the case.
I don't know if E-Hammer is exactly the same as SmartErase.
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