> Your statement uses the presence of bugs to indicate a product is worth using.

This is not correct; "If a product is worth using, then it has bugs." (P→Q) does not imply its converse "If a product has bugs, then it is worth using." (Q→P). Buginess is presented as a necessary condition of being worth using, not a sufficient one.

It does, however, imply "If a product has no bugs, then it is not worth using.".