I haven't read any of the other Clanbooks: I'm not much of a Vampire player. So I'm coming at this as a book that is tangentially relevant to Mage. As such, I enjoyed it.
The history and structure of the Tremere sections were fascinating, showing how House Tremere fared after separating from the Order of Hermes, and how much knowledge of that has been lost by the rank and file, even if the highest ranks of elders still remember. It was well-written and I enjoyed even the parts that did not fit my person interests.
Best of all, it's in epub (easily converted to mobi) and properly laid out with the art to work on an e-reader.