Why dark side?
Basically, from what I've taken from all pertinent discussions and my own experience, desktop flightsims (whether MSFS or X-Plane) are good for headwork and practising procedures (including R/T if flying online) but rather useless (some even say detrimental) for airwork and practising instrument scan.
My recommendations (supposing you buy FSX):
Enjoy, it doesn't come that close to the real thing but can be very immersive and quite instructive. And regarding cost, it's certainly real aviation which represents the dark side
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