Uh... no, no they're not. They are Summoned Spirits, Insignificant.
Not Unique. You can summon 3 a round if you have the Tomes. It's actually a viable tactic when you outnumber the enemy and have a model close to Ramos you want to nuke- Make your last activation Ramos, summon 3 ECs, walk 'em through the enemy. Next round, activate Ramos first, link in to the closest, controlled detonation another, then detonate the linked in one. The thrid one will die and burst automatically. Does a fair amount of unpreventable damage, for absolutley no cost in stones, and is fairly easy to pull off. I managed to kill Killjoy this way, after scratching him a few times with another model.