My understanding is e911 only the 911 operator can find you on a map when you call 911.

Any other phone calls its not enabled

With technology today I think its just to silence the paranoid

Just because I am paranoid, doesn't mean that they are not out to get me.

GPS is always on (911/police/carrier can always find the phone through GPS), and it just a matter of setting what privileges that the other apps/how you use the phone will have using GPS instead.

So on that note, unless you have a smart phone, leave it on, and check with the carrier to find out what program you should use to find the phone if you misplace it.    It will save you a lot of time if you lose it.