I have to confess that I have never done the whole thing in one sitting. Three chunks over a couple of days? Sure. Can't imagine where I would ever get three and a half hours of quiet to give that a go!
Part 2 (which is really lovely) is edited down to a four minute "single" on the Glassworks comp and it was that 1998 edit that made me go back and check out the whole thing many many years after I first became aware of Glass as a composer (which would be 81 or 82). I have been more of a Reich / Adams / Riley fan over the years and so tended to collect the Glass soundtracks but not much else of his but MITP is a kiler piece of large scale writing. I also especially love the soudtrack to The Secret Agent and I really rate the Low Symphony which I know some people (Bowie fans and Glass fans both) are a bit snobby about but large parts of it are really thrilling. And the record with Ravi Shankar is pretty great. I don't think of myself as a Glass fan but I seem to like an awful lot of his music. Not sure that that's about. An aversion to the operas probably.