Don't think I ever want to be in a knife fight. But if I am...I'll probably have my gun with me. 15 rounds > knife (assuming I'm not already getting stabbed).
at the range at which most assaults begin (3-10 feet or so), trying to draw your gun is NOT the proper answer to a knife attack.
People go on and on about the "21 foot rule/Tueller rule" without considering that most fights don't start at 21 feet, they start at conversational distances.