I recommend that you look at Terence's review at http://www.goodreads.com/review/show/250656447 , but I would like to add some remarks to his.
Amongst these plays I much preferred The Persians . It opens with the elderly councilors to Xerxes who remained behind in Susa. They recall the pride and confidence with which the Persian army set forth but now are filled with foreboding and anxiety at the lack of news of victory. The tension between these emotions is very well drawn. The sense of foreboding is heightened when Xerxes' mother arrives and relates a dream and an omen. Then the news of Persia's calamity at Salamis arrives. The messenger recounts the battle - since Aeschylus was probably in the Athenian navy at Salamis (in any case, since the play was written only 8 years after that battle, he surely knew what he was writing about), I found this report to be riveting and composed in a noble and exciting poetry. In their grief they summon the shade of Darius, Xerxes' father (not the last ghost to haunt Western theater), who warns at length against hubris (he is clearly Aeschylus' puppet here). Then the defeated Xerxes arrives to emphasize in most dramatic speech the disastrous consequences of hubris. This emphasis on hubris is, of course, Greek, not Persian. But I very much appreciate that Aeschylus, instead of gloating over the Greeks' victory, empathized with the defeated foe.
This play has none of the frequent invocations, laments and pleas to the gods found in the other plays. I understand that ancient Greek drama had religious ceremony at its origin and only slowly developed its more human concerns, and, since Aeschylus is the eldest of the Greek playwrights whose work has survived, it is natural that there are, seemingly, more such invocations in his work. But, as understandable as it may be, it was a relief not to have to read them in The Persians . And since much of Prometheus Bound consists of such addresses, my pleasure in that play, clearly the most dramatic of the four in this book, was diminished.
Indeed, I find that I disagree with the relative ranking of Prometheus Bound and The Suppliants made by so many. Yes, Prometheus Bound can be read as a rebellion against tyranny, but as such an allegory it is quite thin. The rebellion occurred before the action of the play - the play is actually about the sufferings of those who rebel against tyranny. This is emphasized by the arrival of Io. How much more appealing, to my mind, is the story of a father trying to shelter his daughters (their number, 50, is absurd, but let that pass) from violent and unwanted suitors! And the moment when King Pelasgus realizes how bad of a situation the arrival of the descendants of Io has placed him in is real.
As for Seven Against Thebes , the less said the better. I was not surprised to read, after I had finished the play and felt that the appearance of Antigone and Ismene was superfluous, that Aeschylus' original ending was replaced by this foreign appendage 50 years after his death.