Purchased the PDF version a few week ago and am enjoying it immensely.
In addition to some new combat abilities, backgrounds, merits, and combination disciplines to support the new material, the biggest draws for this book are:
Expanded magical options for Dark Mysticism, Koldunic Sorcery, Setite Sorcery, Necromancy, Assamite Sorcery, and Witch magic, all of which are given some excellent lore entries and explanations. Fans of magic in World of Darkness will likely really enjoy this.
More excellent medieval word-building, including new lore and rules for how to incorporate fiefdoms, knights, and mass combat (more on that below). I am of the opinion that, particularly in a setting like Dark Ages, time period information, mechanical tools, and world-building are critical, as they provide a blueprint for those of us who are not necessarily history buffs to be able to properly create and evoke a pseudo-historical atmosphere in a memorable and immersive way, rather than just feeling like "DnD with Vamps", and I feel like the book really shines in this regard. The entries on knighthood and medieval combat were particular highlights for me.
- The mass combat rules. I feel like these are going to get a mixed response, but they could also be a major reason one might enjoy this. Conceptually, I like them a lot. They offer an opportunity to simulate medieval warfare tactics and to engage in seiges and other larger-scale conflicts (albeit in a cinematic, WoD manner. This is not trying to be a wargame simulator, nor should it be expected), which not only lends itself well to the medieval atmosphere, but also presents a chance at mixing things up on a grander scale than normal. That said, I personally still find them a bit difficult to keep straight after a few reads, so their practicality may vary for some. The book does provide an example scenario that lays out how everything works -- which is most welcome and helpful -- but I personally didn't find them to be the most accessible thing in the world, so I suspect it may take some getting used to for some players and GMs to really make the mechanics shine.
All in all, I really liked this book, and I think that anyone who enjoys magical characters or worldbuilding will find a lot to be happy about.
[5 of 5 Stars!]