Looks like I missed this thread first time around, so I'll catch it on the bounce.
A4: In the Dungeons of the Slave Lords was I think the very first published module I ever played in, at age 9, with my best friend (also age 9) as DM (and running his own character). He'd borrowed the module from his older brother (who was way too cool to play with us kids), and we played it under the D&D Expert Set rules because neither of us knew AD&D yet. He thought the whole 'prisoners' thing sucked so he ignored it and let us go in fully equipped. Needless to say that kind of defeated the purpose. This was definitely not one of my gaming highlights (but after we finished he let me borrow the module to read it, and I was so intrigued and impressed by how it was supposed to play that I was pretty much cured of my adolescent munchkinism on the spot, and also became an almost instant convert to AD&D -- I had to find out about all those unfamiliar spells and monsters and magic items and such).
Years later I ran A1 for my main group of players. We'd just finished up something like 2 fruitless years in Temple of Elemental Evil and I was exhausted. There was a lot of screwing around in the first part of the module -- getting sidetracked, doing all manner of dumb stuff -- and sensing another potentially endless module I put my foot down when they finally reached the second level; I told them I was running it tournament style and they only had 4 hours to finish the level, and then I started a stopwatch. Shockingly, the players actually stepped up to the challenge, worked intelligently and efficiently, finished the module on schedule, and everybody had a great time. This module has several really fun and memorable set-pieces, especially the battle with the Aspis drones on the narrow planks over the slave pens.
Unfortunately, things didn't go so well as we moved on to A2. The party stumbled into the lair of the Ankheg (?) in the outer bailey -- I believe they also managed to trip an alarm and alert the entire fortress -- and got beaten up so badly that they were forced to retreat via Teleport spells. It was a complete disaster, one of the most embarrassing defeats that group ever suffered (well, on second thought I take that back, because that group suffered a LOT of really embarrassing defeats, but this was definitely up there). So, unfortunately, they never finished that module and I never got to run the rest of the series. I did play through the entire series once as a "solo adventure" (in which I allowed my favorite character to lose his suit of magical plate mail to that giant magnet trap in the basement in A2 -- I thought that was very mature of my 11 year old self to do) but that's not really the same thing.