Not sure how many VR-users feel the same way, but every now and then, when I'm driving and the car/track/time of day/weather combination felt so perfect I would've liked to record a video of the onboard experience. Because replay's don't capture the intensity of the actual experience. Those are missing out on the realtime vr-headmovent, emphasized by the fighting of the wheel (and the motion simulator) and the thrills of the driving on the limit, it just wasn't the same. Like pooring a liter of a water in an espresso. Also there's no way to have traffic in a replay, certainly not the exact same as during the actual driving.
Of course there's the VR-mirroring (both the OG version and the enhanced CSP version) but most people will use OpenXR by now and the image was way too distorted and/or zoomed in for me. On top of that, it took noticeable PC-powered resources to drive the OG mirror, the CSP mirror adjustments and having Nvidia overlay for Geforce Shadow on to record the gameplay.
Well I finally took the time to figure out a solution to this "problem" 😅 and wanted to share it to save people (in the same position) some time.
First let's look at the result:
(don't mind the driving, I'm bad at it)
GUIDE:
To set it up you install OBS-studio to record the gameplay:
https://obsproject.com/
After that, you install the OpenXR plugin to directly capture one of the eyes inside the headset:
https://github.com/Jabbah/OpenXR-Layer-OBSMirror
Then you setup OBS - Main settings/recording/streaming. Lots of youtube videos available, I used this one:
And you adjust the captured image to be as little distored as possible. I used this video:
(With this step you can adjust the view to show less car and more road for example)
If you've followed all this, you can disable the OG and CSP mirroring, and of course disable the Geforce overlay.
Some (OPTIONAL) bonus benefits, you can add color-filter corrections directly through OBS. I used this video as a guide:
And lastly, an unforeseen bonus I encountered, when you add your streamkey to obs, you can directly stream to your Twitch-account. I'm not aspiring to become a streamer, but this way the video's don't take any space on my harddrive! Turn on VOD (Video on demand) in your twitch account otherwise your streams won't be saved. I believe they're stored for 7 days if you not an official twitch-partner. You can download the video's from your own account during those 7 days if you want a store it longer on your own hard drive. (You can probably also use Youtube-streaming if you prefer it).
Another benefit is if one of my friends comes over I can send him a link to the video of him driving before he even got out of the simulator.
Note that the best video quality will always be Recording directly to your harddrive instead of streaming to these services. They compress the hell out of your video.
One more tip, when inside the headset, open OpenXR Toolkit settings and adjust the
Shaking reduction to have a little "stabilizer" applied to the video. I've set it to -40% which I got from one of the video-guides.
That's it, you're all set!
I personally use a streamdeck which has built-in obs controls. (OBS does have an option to bind your own shortcut keys.) So now, whenever I'm driving and I feel the need to capture a little clip, I literally press 1 button, and the complete raw experience is captured, uploaded and saved, with minimal use of resources (dedicated encoder chip on GPU, otherwise unused, no large hard drive space needed, no mirroring to monitors needed) and no more distortions than I've settled on. This "problem" I had didn't just get fixed, it got obliterated.
Anyway, I just hope this helps at least one other person.
fighting the motion-simulator and wheel. Unfortunately I don't hold any knowledge regarding NeckFX and it's settings, but I've seen some monitor footage with great shaking-simulation, so it probably can be done. 
