I have used this extensively in my campaign of The Sprawl. You won't catch me without this book while running anything cyberpunk. My printed copy is always next to me at the table if I want to get some details quickly.
Once I needed to come up with a street gang gang quickly, so one roll later I had it (The Screaming Shards, an all female gang that take a bunch of steroids). A bit of improvisation off of that idea and we had a gang that was a staple of our campaign. One of my best sessions ever was about gang warfare and politics, which was between four gangs pulled straight from the table in the book.
Seriously, get this. It is one of the best resources that I have ever used for roleplaying. Be sure to throw the author a few creds, it's so well made that it's a steal at any price.