Well This is better than the House of M core book. The first half of the book is about Wolverine, but really it follows Mystique and is about her. It is mostly her being debriefed by Shaw after Logan ran off. But, it does get into a little world building for the constructed reality. It builds up her and Logan's relationship (they call him James in this story, I've seen him called James in other books before too, but he's Logan to me). It is the strongest story of the bunch, and gives the people with the constructed universe a reasoning behind Wolverine going insane and AWOL. Now, did that need an explanation form their perspective? No, not really, considering it's still crazy, just a different kind of crazy. But it's a pretty solid story, so we'll give it a pass.
Next we get a middling story of political intrigue involving BlackPanther, Storm, Namor, Black Bolt, Quicksilver, Magneto, Sabertooth, and Apocalypse. It has some cool moments, but over all it's pretty weak.
After that, we get to see the fallout and breakdown to Hawkeye learning about his own death. Mileage will vary.
Then we round it off with Cap'n America reminiscing over some alternative history. How this world turned out a little different, and what Rodgers was doing while the mutants rose and humanity fell.
Taken as a whole, it's a decently written bit of world building. Though, none of the stories are strong enough to stand on their other than the Wolverine story, Even together the other stories are middling at best and can't stand on their own without the Wolverine story. But when you add it all together. You get a better written, more cohesive story with better art over all than the core book (not 100% on the art, but it's mostly true)