I have been experimenting with pheromones for a while now. I was a member of Love-Scent long before they came to this board to advertise. There is one thing I picked up at their forums a while back, that some of you may not know.
Pheremones may not work too well for people who already know you. When you spend time with someone, they develop a "Pheremone Imprint" of you. So lets say you already have a girlfriend, and you get a strong pheremone, like "The Edge" to try and excite her. Well, it may not do anything, as she has already developed a pheremone imprint of you.
Now, say that your girlfriend went away for a month and then came back, then it would most likely have a very different affect. It would probably make her extreamly excited/aroused when she saw you again.
This property makes pheromones a great help for meeting new women (or men in a womens case), or for situations as above, but it may not do much for already existing relationship, or even that "friend" or CoWorker who you have been trying to get with for a while. If you are around them all the time, they probably wont have a reaction.
I just figured I would post this for you guys to read, in case you havent spent alot of time researching on your own. Also, this said, I would also like to state that while the pheromones may not have an imediate reaction to someone you know, if you do use them during sex, it still could provide some interesting results for your partners arousal.