ngrain versus unity

a lot of military contract use ngrain for their projects. I find it would be better to use ngrain.
Anybody out there with some experiences regarding this?

nGrain looks more of a training/simulation tool, where unity is more of a game engine.

but what is the strengh of the software of ngrain, i find that everything you can in ngrain works in unity and you can have more control to make your own training.

Unity doesn’t have a stupid name. :o