EE has some fantastic things (alch bags, merc eye, flying ring, condensors) but also has some unbalanced/griefing things (mk3 collectors/relays, catalytic lens/destruction catalyst, ring of arcana, etc,) bugged exploitable items (RM furnace, alchemy chests, black hole band in alchemy bag, transmutation tablets, etc). Overall, its a fantastic mod, but really wasn't designed with SMP in mind. This would of been fine if not for the config being not very flexible to turn off/reduce/partially disable certain items and such. Currently on the server I'm admin on, we've been working with the owner to try and balance EE without removing it entirely. Often that seems the easier option. Players have a bit of a knack of getting around the more vanilla methods, ie, ban RM furnance, but instead they put it down with an auto-crafter and deployer. We've resorted to actually removing the patterns, so items aren't craftable under normal circumstances. This also allows us to use our economy to make these 'restricted' items purchasable, but in a strictly controlled manner.