I haven't been involved in MDI specifically, or any other (apparently) free-standing mens organisation, so I don't have specific experience to share in that. I've been involved in Quest, which is an offshoot of EST, as are many other organisations listed here, such as Landmark, lifespring, PSI, mankind organisation etc.
They share a common root 'philosophy' and set of
Forum:
Large Group Awareness Training, "Human Potential"