See
http://www.eq2flames.com/brigands/40...ar-thread.html and read through, there is some (not much though) discussion about it.
Pretty moot probably with the GU51 changes I would recommend getting all your dauntless. I'm assuming you aren't a raider but even so I expect the x2 raidzone is going to see a lot of pickup action.
If you are that much of a casual player that you don't see yourself ever getting a shot at raid loot then yes, it probably is a good idea to go for 3 piece set bonuses from 2 of the sets. DA proc on chest is nice. Gloves are best til fabled. 3 piece set lifetap adds nice dps. Would recommend the legs as 3rd probably (get WW or SL shoulders)
If I were you I would compare the Wilderness Warrior (yes, it's leather) vs the Soul Lancer for 2nd set.