You will always have to calculate aero coefficients in any aero model, good or bad. It is how they are modelled which makes the difference. Without modelling coefficients how would you construct an aero model? Even X-Plane must use them.
In X-Plane, we design airfoils - like you do in real.
The flight model uses this as a base for it's calculations.
http://www.xplanefreeware.net/morten/DIV/AM.png
Cm, Cd and Cm at different AoA's, Re# etc.
You can use/create real ones (NACA or whatever) or invent your own.
The model will perform accordingly.
There is offcourse 1000's of other variables we enter as well.
Body's are offcourse modelled also.
So, you could say that unlike MSFS, XP has an athmosphere. ANYTHING you put in it will get affected by forces.
This is what makes XP a fantastic "hands-on" simulator. If your main
purpose is flying on AP and pushing buttons, flightmodel is of less
importance. System modeling is, which MSFS is good at.
Cheers,
M