I watched the whole thing as a teenager (probably multiple times) but I haven't seen most of it since then except for sporadic episodes here and there, and it's just such a fascinating experience! I literally remember some things all these years later - the

disturbing spoiler with child harm

dead baby whose mom smothered it to keep it quiet

in particular has stuck with me without my remembering what it was from (I thought it was from something way grittier than MASH!) but also some of the playful jokey stuff; in fact I've realized that some of our childhood games and catch phrases came from jokes on this show. But it's been so interesting to also relate to it as an adult and get a bunch of new things out of it!