MoM and lands of conflict are the only two I own. MoM has a lot of undead templates and some specific WoW demons and variants of standard critters as well as their unique humanoids (nagas, pandaren, various trolls, razormanes, etc.) and it is all 3.5. There is a bit of duplication with the MM (some gnoll variants, a few critters that are only slightly different, etc.) and some are outdated by 2.0 WoWRPG (jungle troll) but it is a good 3.5 monster book and has lists of creatures from other SSS monster books and the MM that they feel are WoW appropriate. Lands of Conflict is mostly a flavor and setting book with not as much crunch stuff. I don't know how it meshes or conflicts or overlaps with the new corebook.