Here is the rankings from the
3rd party poll:
Ptolus (MP) 40.55%
Complete Book of Eldritch Might (MP) 35.94%
Tome of Horrors I (rev.) (NG) 34.56%
Pathfinder: Rise of the Runelords (Pz) 34.56%
Midnight (FF) 33.18%
A Magical Medieval Society: Western Europe (XRP) 31.34%
Shackled City Adventure Path (Pz) 29.49%
Book of the Righteous (GR) 27.65%
Freeport Trilogy (GR) 27.65%
Advanced Bestiary (GR) 26.73%
Freeport, City of Adventure (GR) 25.35%
Dragon Compendium I (Pz) 24.88%
The Banewarens (MP) 24.42%
Monsternomnicon (PP) 23.50%
City of Brass (NG) 23.04%
Rappan Athuk Reloaded (NG) 22.12%
Book of Fiends (GR) (out of order) 21.20%
Creature Collection: Revised (SSS) 20.28%
Tournaments, Fairs & Taverns (ENP) 19.82%
Iron Kingdom World Guide (PP) 19.82%
Relics and Rituals I (SSS) 18.89%
Book of Hallowed Might (MP) 17.97%
Tomb of Abysthor (NG) 17.97%
Book of Iron Might (MP) 17.51%
Iron Kingdom Character Guide (PP) 17.05%
Hyperconscious (MP) 15.21%
Kingdoms of Kalamar Players Guide (K&Co) 14.29%
DCC#28: The Adventure Begins (GG) 13.36%
Testament (GR) 13.36%
Denizens of Avadnu (IC) 13.36%
Witchfire Trilogy (PP) 13.36%
From Stone to Steel (MG) 11.98%
DCC#51:Castle Whiterock (GG) 11.52%
Deluxe Book of Templates (St) 11.52%
Creature Collection II (SSS) 11.52%
Lost City of Barakus (NG) 11.06%
Psychic's Handbook (GR) 10.60%
Advanced Game Master Guide (GR) 9.68%
Advanced Player Manual (GR) 9.22%
Occult Lore (AG) 7.83%
DCC #3: The Mysterious Tower (GG) 6.91%
Monster Geographica: Forest (XRP) 6.45%
Plot & Poison (GR) 5.99%
Second World Sourcebook (2W) 5.99%
Torn Asunder (BP) (out of order) 5.53%
Book of Broken Dreams (Bls) 3.69%
The Fantastic Science (ENP) 3.69%
Wildwood (BP) 2.30%
Iron Kingdoms did not do terribly. But not great.