This profile was added in early December and is marked as “Fair”; I currently use a custom A21N airframe with an altitude offset, fuel factor and updated weights.
I am curious whether there are cases where the old approach (A321 + tweaks) might give more accurate results than using the new A21N profile (and if yes, what those cases would “be”)?
The A21N profile was extrapolated from the A20N, which itself is already based on very limited data. Hence the “Fair” label.
I haven’t actually tested it with any add-ons in particular, so I can’t really answer your question. My instinct would be that if you have already tweaked the A321 profile to match the add-on you are using, that will probably be more accurate.
The true A21N profile might have an edge in situations where you are intentionally flying below the optimum altitude, for example. But I would say that if you are happy with the accuracy of your tweaked A321, just keep using it!
With the release of the ToLiSS A320neo just around the corner, I noticed SimBrief.com - Aircraft Types actually lists the accuracy of the A20N profile as “High”, and that made me curious, given the above statement. I guess there’s no category between Fair and High that the A20N profile could/would fall into?