I'm curious to know if any of you have actually bought/owned a tester? Every tester I've had was significantly different from the original fragrance.. as I said many posts ago "lifeless"
Why yes in fact I do own some testers! And they are all exactly the same as the original fragrances. One doesn't even have a cap, and it is perfectly fine. I fail to see where the logic of air tight caps is coming into play. Most bottles of fragrances I own the caps are FAR from air tight. Like stated before, unless you have a splash or massive flacon of something, chances are if you keep it out of sunlight and heat, it will be pretty much safe. If you are going to get super technical about everything, which it seems like you are, there is no doubt a fragrance is going to decay over a period of time. I don't think it is a world crises though, causing it to evaporate within a month. In fact, I feel much safer keeping my Hypnotic Poison Elixir stored with the spray pump attached then taking it out/off everytime I want to spray and replacing it with its "airtight" cap.

Anyway those are just my thoughts on the subject. I think technicalities took this uber far off topic :X