You asked for our opinion and mine is "No". Let her decide to do it when she wants to. Obviously you aren't going to have a problem if she is 4 or 14, since you're willing to do it now.

I think I had mine pierced at 13. I don't remember asking to have them done before that. I sort of held 13 as the age that I would allow Helen to have hers pierced, but ended up caving in when she was 6. But, it came in handy as a trade off with her. She continually got up during the night and got in the bed with me and did the same thing when she was visiting her dad and stepmother. He and I agreed that she could do it, but she had to go one whole month without leaving her own bed at night. And she did it! So she got her ears pierced. I have held firmly on no more piercings in the ears until she is over 18 and can decide for herself, then. I did allow her to have her belly button pierced this past November, though. I required her to pay for it herself.