The use of "canned" UAs I have always found dreadful and counterproductive (other than for box-ticking purposes).
I echo Centaurus' comments.
From that skill position, as the skillset improves, I have always found it useful to have the pilot close his/her eyes while I put the aircraft into whatever progressively ridiculous position so that, on eyes opening, the pilot is faced with a dynamic, time critical situation requiring very rapid data gathering, assessment, planning and execution.
Invariably, the initial exercises are a bit tatty but almost all progress rapidly. A critical secret to the tale is to make the environment non-threatening so far as the instructor is concerned so that the pilot doesn't waste cognitive effort on "what is the guy in back thinking" and puts all his/her effort into the task at hand.
The comments re sim fidelity and modelling extrapolations are noted and very pertinent. However, providing that the sim presents a "reasonable" picture to the pilot, it still can be useful as a generic training aid in UAs.