Tree, honestly the sound in the videos is not realistic.
"What? It's recorded in a plane!"
Yes.
But:
1. It's much too loud for full spectrum recording with a normal camcorder. You can hear the microphone in the Mustang-Video is suffering badly.
2. If the camera is also attached to the cockpit, the noise is much different from what you actually would hear.
3. You are not a camera. You are a pilot. You wear protection with built in phones.
4. You don't know what was done to the sound after recording.
5. You most likely still have the opportunity to crank the engine sound up and the other sounds down. Together with a good sound-system, that's your key to do whatever you want with your sound.
Just a little different example on reliability of sources:
In this video, the in-cockpit-sound much closer to the sound in IL2 than to the sound in your video.
