This is a pretty good expansion, with a great and emotional story to add to the already emotional story of the main campaign. I think it isn't 100% needed to fully enjoy Cyberpunk 2077 (unlike Witcher 3's Blood and Wine expansion).
There are some nice missions in this expansion, and some of the spy stuff reminded me a lot of James Bond and even a little Metal Gear Solid. The new characters are interesting and they all have two sides to them. It makes them all pretty unique.
So the main story of this is pretty good, the downside is Dogtown itself. It really doesn't look any different from other parts of Night City, sure it looks a tad bit more "Mad Max" like, but it isn't like Witcher 3's Toussaint map, which was almost the completely opposite of the dark and bleak world of the main game. Dogtown isn't interesting, there isn't anything cool to do there, and I thought this expansion was gonna open up the map more towards the outer top right area (since it was blacked out in the original).
Also Dogtown is extremely, extremely small, you can drive through Dogtown in maybe 30 seconds if you were to just go straight. I can't express just how tiny Dogtown is. Just imagine maybe 7 - 10 Night City blocks (squared).
Anyways, it adds a new but depressing ending, multiple choice regular endings, and a few cool missions and action set pieces, especially one in an airport (that is all I'm gonna say).
9/10
(I recommend fans to play this game, but casual players can probably get through Cyberpunk 2077 without going through this story)