This is a great video to demonstrate the differences in those AWD systems.
It is too bad they didn't also show a real 4WD system just as a comparison.
A real 4WD system (like on 4X4 pickup trucks and Jeeps) with a lockable rear axle will be just as good as the Subarus. I suspect that the rear differential gets locked only when you use 4X4 L mode though... not sure that the rear axle gets locked when shifting from 2WD to 4X4 mode at freeway speeds.
Due to the rising cost of ammo, do not expect a warning shot! Sorry for the inconvenience.