After a childhood drooling over A4000s, I finally got one in mid-2000, but then had similar problems to the ones you are describing - regular lock ups, random resets. I just could never trust it so was never able to use it for important work. I also wasn't keen on how generally chunky and cheap it felt. It put me off Amigas for a while, to be honest. My A1200 was always rock solid though.
