DRM-free for users of legitimate installations Means the DRM is still there to verify that, so its not DRM "free" at all.
Massive flight model upgrade (RotorLib 4.0) You can put wings on a brick but when you check it's still a brick.
The flight model upgrade is a joke still, some issues fixed, some others (elementary things) are not in. Also helicopters still do not fly nor land like real helicopters... It seems BIS doesn't understand the physics of the effects involved, or can not code them in a real time sim.