3G vs. EDGE on battery usage while on standby

[iBoxtaboy]

I know 3G uses more battery resources than EDGE when you're using it, but how about when your phone is on standby? I notice that if you're out of WIFI range, your phone defaults to either 3G or EDGE standby depending on what you have it set to. Will you get longer standby if you turn off 3G?