that some of those updates cover security holes that have been found. I have ME, and have always downloaded every update. The only problems I have had, were always caused by a new application or software being loaded. The problems stopped when these were uninstalled. One of these, funny enough, was Norton AV.
I suppose it's like anything else, someone is always having trouble with their new car, or washing machine. Even though they are all off the same production line. Funny old game innit?