It was... almost insanely tough. We almost got TPK in the first room. I don't see how a team could survive unless they metagame and have a certain buff before going in.
Maybe the spawns in the first room could be lowered? I'm not sure if the spawns were bugged.
I'll just throw in my observations since I was there: It likely scaled up a bit more with me there, and it seemed doable if we had used some better tactics, bit more supplies, and a better combined total of levels among us.
At least the parts we saw anyway.
Also I could be wrong, but I think this is one of those quests that isn't meant to be easily done, or all of it's secrets reveled quickly....
I have to go with KreShar on this one. I was with a group of about seven and we didn't make it five steps into the quest before being swarmed and pwned. I don't mind very difficult quest, just not the point of entry.
Fairly sure there is at least one bug. At least, I've yet to catch a group attempting but the shadows (one or two per PC) should only appear every 60 seconds or so.
I fiddled with this quest a bit. For what it's worth, I'm confident that in time players will discover that the rewards are definitely worth it.