I can't speak from experience, because I've never been attacked or even threatened, but some of the statements made in this thread just don't seem right to me.
Time, distance, and money have prevented me from attending any of the reputable training schools but, like most of you, I have taken the opportunity to learn as much as possible from watching and listening to Bane, Ayoob, Wilson, Head, Janich, and many others. I must admit that I have NEVER heard any of them say that a non-lethal response is a waste of time. I have NEVER heard any of them say that if you're attacked with fists then respond with a Howitzer. I have NEVER heard any of them say that when you're attacked then your stated intent is to kill.
Far be it from me to judge another's reactions... for you may have indeed caught the glare of an attacker's eye... but some of the opinions given in this thread are counter to all that I've learned and would be legally indefensible in many jurisdictions.