gives a good updated look at the sons of ether in revised, it's less annemic than the 1st ed SoE book and you get a really cool fiction story explaining the whole tradition in depth. it moves beyond the pulpy-paradigm of the 1st ed and shows how the etherites work as a complex organization, it takes them out of the realm of science-fiction and instead displays their real academic institutions and politics.

the only complaint is that this is kind of a halfway point between the older editions and m20, where the etherities in m20 have now become more inclusive and less gendered. this still treats female ether scientists like a small political faction instead of a huge part of the organization, so you should read m20 to understand how far the tradition has come since the days of victorian misogyny. other than that, this is a great sourcebook for players and storytellers.

An updated Sons of Ether book is a good thing for those who play Mage: Revised, but for those who like the 1st and 2nd edition SoE there's less here.

The major changes between editions were changing the history section and teaser story to fit the new plotline and adding Merits and Flaws appropriate to the tradition. The story is pretty good, but the Doc Eon story and Paradigma excerpts were more enlightening. Of the two merits, one is a very conditional merit and the one flaw is fine but also somewhat duplicative of other mage merits.

On the other hand, this version of the SoE book does a better job explaining the factions and listing their members.

Neither this version nor the original version was great on rotes or how the SoE see spheres, but that is hard given their archetypes.

The choice between which SoE book really is going to come down to which story you like best unless you want a SoE-heavy game in which case this book would be recommended for better coverage of factions.