I tried in VR only. It was not working before, with Proton 5.0-9 and others, it started worked recently with 5.13 and it works perfectly, although the VR control scheme is weird (you have to push the Index stick up to select, instead of pressing a button) -- but it is completely playable, once you get used to it. Also, it seems you can't turn using the controls, you have to turn "for real". Probably someone on Steam has already published a control scheme that "fixes" those issues.