I thought it was a well-balanced documentary which did a good job of getting across some complex technical concepts. Presumably they made use of a 320 sim because that was the closest type they could get hold of within their timescale? At least they didn't use a Boeing cockpit!
With regard to their statement that AF447 was the only flight to go straight through the stormband, I actually thought that was reasonably close to the facts as they emerged at the time? Other flights seem to have picked their way between bad areas, and I seem to recall at least one other pilot expressing surprise at the route followed by AF447, going by their reported track.
There was also a lot of discussion here about using weather radar. I thought the program made rather less of that than I would have expected.