Question VR Headset with motion compensation

Hi everyone!
Together with a friend of mine I'm working on a 2DOF + traction loss motion simulator for playing driving games (mostly Assetto Corsa and ACC). We would like to try out VR but I don't have any experience on this technology. Our main source of concern is the need of motion compensation.

Reading here and there (also from this forum), I understood that the best option would be having an headset with external sensors so that we can attach them rigidly to the frame of our rig. This, in contrast with using a compensation software, should be future proof (meaning that we should be immune from potential future updates of some VR-related software that could break everything).

Summing up, I've some questions for whoever has some experience with this platforms:

1. Does it exist right now an alternative option that makes use of compensation software which is comparable to using base stations mounted on the rig?
2. How's the experience of VR motion simulation with external sensors fixed to the rig in 2021 compared to using an additional software for motion compensation (from the point of view of setup and daily usage)? Namely: what should we expect if we follow this route?
3. Am I right if I say that our main options are the HTC Vive PRO/Cosmos and the Valve Index? Are there other headsets that make use of external base stations?

Thank you in advance!

Thank you for the reply!
So you're saying that we're forced anyway to use the OpenVR-MotionCompensation software, hoping that such a hack will continue working also in the future. But if there's no alternative, then no problem, we're going to experiment on this going step-by-step.

Talking about which VR system to choose and buy, we're limited to systems that require base stations and, at the same time, we need to buy the controllers too. We'll have base stations fixed to a stationary mount so that they can both see the controller and the headset.

Would that be our best option? On the OVRMC website there's the "Tested devices" page with a compatibility table. I'll refer to that one in order to choose.

Is what I said right?
Thank you very much again, I may come back here with further questions in the near future.

There's also Pimax that has reference tracker motion compensation built into their pitool software. I haven't used it in a while, but it's very responsive but doesn't have filter options like ovrmc so you have to take care of any vibrations with a good mounting solution. I don't believe it breaks with updates to the steam input system because pitool does the compensation before sending the position data to steam. Eventually we might get an openxr version of ovrmc or something similar someone else makes for openxr.

If you keep the motion to a small range (say +/- 5deg), Oculus Rift-S works fine without compensation. I think humans (and chickens) have a tendency to keep the head upright, so I personally don't have a problem with VR tracking but I'm also using small angles.

Kinda like in this video

I use the Valve index and use the controller for motion compensation, it is very easy and works well. I only play DCS so I can't attest to other games, however for my 2DOF rig and in regards to flight sims, motion compensation is a necessity.