Our party finally mustered up the nerve to take the gob on, who spawned a few hours after we had been cleaning out the area of its goblins. The highest member was one 60 DRK, everyone else was 58-59. Full PT make up was RDM BRD WHM DRK DRK PLD.
The melees went into the fight with full TP, and as the fight began the BRD used his spinning disco ball two hour. The NM was hitting the PLD hard (100+ a hit) so at first we thought we had made a mistake, but with mage's balland + refresh for MP we were able to keep his health within a safe range. The DRKs used their two hours in conjunction with SE, but as far as I know the WHM never had to use beni.
At one point the taru WHM got aggro, when the mob had 1/6 of its health left. The NM seemed to ignore the PLD's invincible, but through the grace of stoneskin + blink, the WHM survived. At the end of the fight, the WHM had a little less than 100 MP, I had 79. No deaths, it dropped 1000 gil each and a gold beastcoin.
If you can easily chain the gobs in that area, then I would say your party has a good chance of taking it down. I think a BLM or RNG would have pulled too much aggro, so in their place I'd suggest having a dedicated backup healer to assist the WHM, since the mob hits hard. I threw in paralyze and slow on the NM, and hasted the DRK..but for the rest of the time I was either refreshing or helping the WHM cure the PLD.
All in all it was a fun fight, and a nice way to end an XP PT.