It is has just the right amount of "typical shoujo" elements, sci-fi and drama. There are quite a few characters to keep track of though and that can be a bit confusing at first, but shouldn't be a problem anymore after a few chapters. All the characters (past and "present" forms of the main cast as well as other characters joining in as the series goes on) are interesting and to some extant relatable. Everyone should be able to pick a favourite and you really feel for them while reading and learning more about their past and present situation.
I highly recommend this series to everyone who enjoys shoujo as well as sci-fi stories and likes being surprised by a series - because (for me at least) PSME is full of surprises and turns.
I rated the artwork with "good" (while everything else with "outstanding") because this series was published in the 80s and 90s and... you can tell by the artowrk. Especially in the first few issues. But it is very interesting to see how Hiwatari Saki's skill as a mangaka improved a lot while she worked on this series.
