I started going through my wishlist on IFDB, and this game has been on their longer than any other, because it was so intimidating I put it off. I ended up playing the ifarchive version, which uses local browser storage for saves.
I played for a while, using in-game hints and getting < 20 points out of 365, then used a walkthrough and maps from several different sites, including CASA. Even then, it was difficult to follow and required solving some puzzles independently.
If you had to play just one IF game for a very long time and didn't have access to any other, but could talk to other people, this would be a great game, because it's designed for long-term group play.
Many factors make it large. First, it has a giant map with many diagonal connections and cycles in the graph structure, and doesn't list exits automatically (unless I missed a command to turn that on; I just used the EXITS command), and this giant map exists in multiple time periods at once.
Second, many of the puzzles rely on pun-based commands, requiring a leap of intuition that can't be solved with just brute force.
Third, and perhaps most importantly, many actions have long-delayed consequences, and many items are used in scenarios quite different from the ones they're found in.
None of these are bad game-design wise, but they mean that you will spend a great deal of time on this game in order to experience its content, while many current IF games are designed to be completed in one or two sessions with little 'friction', due to the multitude of competing games and other reasons.
The plotline is buried at first but becomes stronger and stronger, especially once time travel is allowed. If the author created the first areas first, it would explain why the game starts with a mishmash of silly things (including a tortoise and a hare on a Moebius strip a suspension bridge that suspends you). Later areas have strong thematic consistency, especially the future world. There are a few other threads of plot that weave through the game consistently, like the use of opiates to expand the mind and a meteorite that makes several appearances.
The game isn't mean; it increases difficulty in generally fair ways. Hints are provided in most rooms, and a helpful friend gives you more and more commands over time that help out in a meta way (I loved FIND [ITEM] because it moves you to that room, enabling fast travel).
This would be a great game for a let's play or other group-based activity, since finding the right phrasing is good.
I don't think I'll play it again, because I just struggle with its style of expansiveness, but I enjoyed my time with it and think many others would as well.