I have unplugged and replugged in my 1K's and 400 several times, foolishly that is, but 10 months later I am still getting the same results from them. I am about to change them out none the less. I have both digital and magnetic. One time I did have a scare though, my 1K came unplugged and I plugged it back in real quick and the bulb sounded like it was boiling and bubbling inside, I did unplug it then and wait about 1/2 hour. That was over 8 months ago and I still am using the bulb.
Adieu