The original "G" series (G1-2-3) is, in my humble opinion, one of the best adventures ever produced for Dungeons and Dragons. This product contains those adventures and then expands it to include Part Two: The Liberation of Geoff. The second part of the module details many areas of Geoff, includes histories on the towns as well as their current state. It includes a handful of dungeons that are, for the most part, interesting. The only problem is that it can become somewhat monotonous when the vast majority of things you fight are ogres, trolls, and giants.
If you do not own the original "G" series, then this is definitely a pick-up. If you do own the original "G" series, then, well... I would still buy it. But, then again, I am a big Greyhawk fan.