Englishal,
I don't think anyone is suggesting that M$ FS flies like a real a/c. Rather, that it can provide the opportunity to learn & develop some of the skills that make up the sum of the pilot's repertoire.
For this to be beneficial then I believe it must be part of a course, not just J.Bloggs installs it, uses it a lot & then believes he/she should expect some reduction in a/c training time. If anything, this would lead to an increase in the minimum training necessary to qualify.
As with most things aviation: He who teaches himself has a fool for an instructor.
M$ FSim just increase opportunity to be a fool.