I reviewed this book on YouTube here.
The gist of it being that overall the book is good. But that the book really needed to flesh out the Cowled Wizards more. Them banning all arcane magic (which technically means more than just spells) actually affects artificers, bards, sorcerers, warlocks, and wizards. The fact that the book doesn't meaningfully address this is a big oversight.
In fact, they are the biggest challenge with running anything in Athkatla. So the book should have at least included them as a patron as a way to let the party operate normally.
The maps are good but their numbering is terrible and it can be difficult to find places because of it.
Suldenesselar's section has inconsistencies over who runs it (is it Irenicus or Ellesime?) and is 90% talking about Shadowfell Suldenessellar.
Ust Natha's section is too small to be much use.
The group patrons and villains are cool. But most of the monsters and many of the patron contacts are just reprinted from Heroes of Baldur's Gate (aka the art and statblocks). A lot of the art also comes from Odyssey of the Dragonlords too apparently.
Then there are the proofreading issues. This book has a lot of typos and oversights. It's really not at the level I would hope for a WotC product. In most cases its minor things but it adds up. I made a list of all the proofreading issues that other people and myself have found.
Also, it's been over a month since they released this and they haven't updated the product or even responded to a single post on the discussion section. Which makes me think they have no plans to ever update the books numerous typos and proofreading issues.
[4 of 5 Stars!]