I've been playing the past few months in the Castle of the Mad Archmage, by Joe Bloch.
Man, that place is a maze. It has some cool rooms, but the maze-y tunnels are really tedious. I mean, really. They're hard for the DM to describe, and they're hard for me to map. I'm free-handing it on a blank page so it's not like I'm struggling to get the angles to match my graph paper or anything, it's more like this back and forth where the DM describes a meandering hallway and when we're not sure we understood which direction it turned because it made several snaking turns in succession so we ask for clarification, then the DM re-explains but he's not sure which section of hall we're asking about, and after several questions we finally back up to find a common starting point to describe it again and then find the DM backed up to a different starting point because the halls are all over the place and something like "where the long hallway turned left, where did it go from there?" isn't clear enough for everyone to think of the same place. Multiple times today the DM had to just show us the map to save time.
Honestly, there is a line where the mazing stuff just isn't fun, it's work. Of course this is the Castle of the Mad Archmage, so maybe it's just because so-and-so wizard is crazy. I can accept that as long as there's something sane to compare it to in the world. It's not madness if there's no sanity, as the tent-pole to a campaign it's all there is. I do get the idea that realistic caves and underground tunnels don't have straight lines and right angles, but there's this other side too where we really just need to hear and understand the layout quickly so we can get on to the fun parts. We're adults with kids and jobs, we only have a few hours in a month to play as it is.
Maybe if we played differently it would be better. Maybe if the DM drew a map for us, or had physical set pieces or we used miniatures, something to make it easier to communicate. But we generally play straight "theater of the mind", so easy descriptions make a difference.
So, while yes I am having fun, let's just say this is not my favorite megadungeon. If the DM provides any other options I'm outta there.