How effective is the first response curved handle??

I'm only asking cause I have heard people say it has gave them false positives well I tested this morning and I'm trying not to get my hopes up because I got a positive im just waiting to see if AF shows her ugly face Saturday... I've just seen many post on here about them giving false positives... cause I don't have hardly any symptoms so I feel like that I may have a false positive anyone else???? Have this happened