In this clip, there are some good examples of non-cooperative, ballistic training. It is about as good as it gets and still keeping it safe...hence all the gear.
Anything short of this and you really have too many contraints and rules for safety. It doesn't take guys too long to figure out how to take short cuts and exploit technicalities and the rules.
It is all good as long as we keep in mind the shortcomings that the constraints we impose create.
It is good to get exposure to as many different scenarios and situaitons as possible and figure out how to gain skill.
It is why I am now doing Judo as well as BJJ and Aikido. Each offers their own set of limitations and constraints, but because of them, you can develop some very good technics and skills in particular areas.