I know Wanderers Palace does work(found out originally when taking my Squadron through there, and then testing it myself...roughly 10min runs soloing it as an AST). Don't ask me why, but it just does/did for me for some reason.
Printable View
ARR Dungeons DO work....as well as HW.
Just an FYI.
Key here is to remember that you need to A: Use your weapon B: make sure its equipped prior to starting boss fight? (maybe?) - honestly it wasn't that big of a hassle to leave the thing equipped non-stop.
I spammed brayfox longstop with A4S? (I think it was 4..its the refurb boss fight) myself..but that's a white mage.
That is the most important part. You can run the entire dungeon with a i340 weapon if you want, but must fight the boss with the relic, since when he dies that's when you get the aetheric condensing part. Though, with the i260 you have at that point for the farming, you have more than enough damage output to kill things fast(the Tonberry King was at about 20% after Combust II was at 1sec remaining...that's without an active card boosting my DPS, and constant Malefic III)
I got density from running 2.5 patch content (WP HM) so it is not just HW content.
Last update they added ARR content. But don't bother with Astragalos as it doesn't provide light but Frontlines do. Why Astragalos doesn't is beyond me.