On our vintage A300-B4s, the door handle has a warning system that sounds a "Beep" and illuminates a red light when the handle is pulled about 10 degrees, if the slide is still armed. Do the newer types have this feature?
I always pull the handle a little bit and wait a moment before pulling all the way. I have once had the warning alert me to a slide not disarmed!
I have seen several slides blown in my 40+ years in aviation including the one on "Air Force One" shown on CNN.