From my experience in fragrances (over 8 years), I have come to understand that testers are the exact fragrance that comes in the original box only without the standard retail packaging. It is of the same potency and chemical makeup of the original fragrance. The reason for making testers is to allow retailers to demonstrate their product for consumers.

I would refrain from buying a tester as a gift because of the plain cardboard box and no cap but I wouldn't mind purchasing them for myself.

Hope that provides a little clarification