Well, you never know, really. The software did "work" (for two days!) It is probably overkill, just to be sure no one could lift my passwords for my financial accounts and such, but there isn't really any way for me, given my skills, to be "sure" that someone "can't" get my passwords. I just "hope" they can't.
What I did, by the way, was create a new user account, made it administrator, and then deleted our old user accounts. I uninstalled software and deleted all my data files (of course), and then ran the software to wipe everything it knew how to wipe, presuming that (1) all my old passwords would be stored in my user accounts or in data files associated with applications, which I deleted, (2) and whatever storage used for my old user accounts, and the apps and data files I deleted, was part of what BCWipe wiped.