My daughter has iPhone 5S with Find my Friends activated. I find it rather buggy. It does not "stream" location so for example if she is on bus and I try to check she jumps off on the right stop it goes something like this: Now I can see she is 500M from her bus stop, Updating.... cannot locate.... updating... cannot locate... after few minutes... Doorbell rings, oh she is home now and app also show her location is home.
Not exactly pleasant experience as a parent.