As Shawn has mentioned,
Precision Response Training also teaches classes that include scenario training, force-on-force training, or scenario training
with force-on-force training depending on the class.
Yes, we use AirSoft gas guns (and SIRT trainers) in those cases as opposed to Sims or anything like that. As several people can tell you, those gas guns are no joke. True, they aren't firearms. However, pellets coming out at 350-450 ft/sec are no fun, either. (Which actually, makes them rather like .22 CB rounds.) The gas guns (unlike spring guns or electric ones) have reciprocating slides, at least a tiny bit of recoil, and actually make a fairly loud noise.
Overall, it means you can work with something that in a minor way acts like a firearm--but isn't. And you only need a good helmet with facemask to use them. (If you get hit anywhere else it leaves welts that hurt quite a bit, but you don't need overall protective gear.)
As Shawn said--the realism of the scenario and its actors far outweigh anything else with respect to training of this type. I've heard any number of people talk about high stress, emotional reactions, and difficulty of response even in situations in which they KNEW the other actors wouldn't even be touching them.
I know that the scenarios I run are all taken directly from actual (and common, for at least the lower level classes) situations. I assume 88 Tactical does the same.
I will say that while I strongly suggest scenario training for anyone interested in self-defense, and that force-on-force training is a very good idea---I don't consider it "essential to truly surviving situations". Plenty of people each year survive and succeed in self-defense situations with considerably lower levels of prior training. As such, it isn't "essential".
For most people, I'd first suggest going to a shooting skills class, to get the basic techniques down solidly, so that you are competent and quick with your self-defense firearm of choice.
That being said, I
do certainly agree that scenario training (and force-on-force) can make a huge difference in people's ability to handle self-defense situations, and the stress that comes with them. As such, I really wish more people WOULD undergo scenario training. For most people, it is a real eye-opener.