Just got done watching MOX on our server wipe to DT for hours on 5 stack. They had a 24 man raid w/ some outside healers assisting and still wiped to the insane dmg. Seems like bioware might have overtuned this encounter a bit. Really not worth all the wiping for old tier of gear.
Damage is indeed OD, still doable, mistakes can't happen or you fall behind and healers can't heal after 50%. Majority of the time you have to have a perfect pre 50% phase or you die shortly after to screech.
The combined factors of move out of the spikes, screech, and lag makes the after 50% phase terrible.
Fight is very doable, we got to 22% of three different occasions. Trick is staying alive after 50% and healing through screech/ not dying during dps down phase due to lag. I at times on a gaming computer would drop to 10 FPS and would cringe when I saw screech.