[D&D]"Complete" books: worth it?

[Wardo]

Unfortunately, both Malhavoc's Unfettered and AEG's Duelist are better takes on the concept.

In which book would I find AEG's duelist? Thanks!

 

[DungeonmasterCal]

They can also steal resistances and other magical qualities.

My only complaint with the Spellthief is they can't steal by making a Sleight of Hand check. The Book of Roguish Luck from Malhavoc Press' Guttermage fixes this.