They hold up incredibly well. The passage of time has not diminished the power of his prose. Mona Lisa Overdrive is next.
I don't remember reading the books together all at once. I've owned them for years, but reading them again as an adult (living in the future) seems to be different than when I read them as a sheltered teenager. For one thing, I'm actually bothering to look up every one of the words I don't understand this time – I admire Gibson's creativity and the breadth of his interests and vocabulary. I've read Neuromancer many times over the years, but I've only read the others once or twice.
William Gibson's cyberpunk novels changed my life. I've been looking back at the cyberpunk era (triggered by the upcoming launch of the Cyberpunk 2077 game, I think) and few of his contemporaries' works can compare to Gibson's trilogy. I didn't even consider the books a trilogy (and the publisher has never numbered them as such), but the linkages are more apparent when you read them back to back.
I've always found the covers for Mona Lisa Overdrive to be cheesy – I found this beautiful image on Google (art by Vladimir Manyukhin):