For a real, simulated environment test, I'd need a lot more power and technology than we have available. A good goal, mind you, but we've got more important things to make than a Holo-theater.

Mostly, what I'm thinking is just a small, walking course, with targets set up all around. The person running the course chooses which targets to pop up, and the person challenging the course has to take the targets in a timely fashion.

More advanced courses often have recognisable friendly targets so as to teach people that not everything that pops up is hostile. Teaching someone to shoot at a moment's notice isn't a good thing if they shoot a scared little boy that runs out of a hiding spot, after all.