It depends on what you mean by "good." If you're asking if they stop working when tampered with, I would say yes, unless they are very shoddily made. Typically, tamper-evident RFID labels work in the same way that regular tamper-evident labels do: There is a layer that cannot be easily removed, so if you peel it, one layer comes off and one stays behind, thus indicating the label has been tampered with.
The trick with tamper-evident RFID labels is to put the chip on the layer that stays behind, and the antenna on the layer that can be removed. This results in the connection between the antenna and chip being severed, thereby rendering the tag unreadable. Therefore, it cannot be transferred to another object. I have never heard any company or government agency using such tags complain that they do not work as advertised.
If "good," on the other hand, means can they be read from a mile away, or some other criterion, then no, they are not good. Am I starting to sound like Bill Clinton: "It depends on what the definition of 'is' is?"
—Mark Roberti, Founder and Editor, RFID Journal
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