I went in with both of my heavyweights, a fire/time corruptor which can lead as tank in ITF 4/8 along with fire farming solo with EBs and whatever else you could throw at it (4 star TFs included not as lead tank though), it didnt last 5 seconds solo in there, my widow which is built about the same lasted maybe 30 seconds and that was with demonic aura up on top of everything. I wasn't using any of the beta buffs. I didnt see a single person in there who was able to solo anything reasonably, tanks/brutes included. I brought along one of my friends with their built tank, we managed to last 5 minutes or so before failure.
Later that day I decided to form a team, it seemed that at about 4 people you could get through the mobs with reasonable certainty that you would not die, had MM use bots to take alpha, I then went in and gathered aggro and the other two on the team a scrapper and a widow wittled down their hp. Lasted about 10 minutes until the Minotaur showed up and basically insta killed everyone, its also worth noting apparently he can do -MaxHP to you which sucks but I think the warning for him being on the hunt needs to be red not grey, grey really doesnt give you the sense of urgency that it should considering how much of a threat he is to everyone.