I think that 1980 and 1981 are transition years in regards to AD&D. The AD&D line in 1977-1979 was pure gold. In 1980 spots started showing in the module line-up:
A1 Slave Pits of the Undercity
C1 The Hidden Shrine of Tomoachan
C2 Ghost Tower of Inverness
Q1 Queen of the Demonweb Pits
S3 Expedition to Barrier Peak
While I hold C1 and S3 to be pure gold, C2 is mixed (some great stuff in the module, but the overall module is rather "thin"). Q1 is a HUGE let-down after the masterful D trilogy. While I know a lot of people like the A series, I don't particularly care for it.
Here is the line of 1981 modules:
A2 Secret of the Slavers Stockade
A3 Assault on the Aerie of the Slave Lords
A4 In the Dungeon of the Slave Lords
D1-2 Descent into the Depths of the Earth
G1-2-3 Against the Giants
I1 Dwellers of the Forbidden City
L1 The Secret of Bone Hill
U1 The Sinister Secret of Saltmarsh
Here we have reprints and the rest of the A series. Hmph. I never cared for the U trilogy. I'd say I1 is the best of the bunch. I've never read L1.
Also, even though the Fiend Folio wasn't published until 1981, I think it was essentially finished in late 1979. The FOREWORD is dated August 1979. DDG (which was published in 1980) references the Fiend Folio. I think it was just publishing hijinx and screw-ups that made the FF have a publication date of 1981 instead of 1979 or 1980.
Here is an excellent chronological list of AD&D products:
http://www.dragonsfoot.org/forums/viewtopic.php?t=15120
A1 Slave Pits of the Undercity
C1 The Hidden Shrine of Tomoachan
C2 Ghost Tower of Inverness
Q1 Queen of the Demonweb Pits
S3 Expedition to Barrier Peak
While I hold C1 and S3 to be pure gold, C2 is mixed (some great stuff in the module, but the overall module is rather "thin"). Q1 is a HUGE let-down after the masterful D trilogy. While I know a lot of people like the A series, I don't particularly care for it.
Here is the line of 1981 modules:
A2 Secret of the Slavers Stockade
A3 Assault on the Aerie of the Slave Lords
A4 In the Dungeon of the Slave Lords
D1-2 Descent into the Depths of the Earth
G1-2-3 Against the Giants
I1 Dwellers of the Forbidden City
L1 The Secret of Bone Hill
U1 The Sinister Secret of Saltmarsh
Here we have reprints and the rest of the A series. Hmph. I never cared for the U trilogy. I'd say I1 is the best of the bunch. I've never read L1.
Also, even though the Fiend Folio wasn't published until 1981, I think it was essentially finished in late 1979. The FOREWORD is dated August 1979. DDG (which was published in 1980) references the Fiend Folio. I think it was just publishing hijinx and screw-ups that made the FF have a publication date of 1981 instead of 1979 or 1980.
Here is an excellent chronological list of AD&D products:
http://www.dragonsfoot.org/forums/viewtopic.php?t=15120