I picked up Mervils based on the recommendations in this thread and elsewhere, and I have to say I came away a tiny bit disappointed. It plays like a really ambitious grad school project, or a proof of concept for a more polished game. Some neat ideas, and plenty of content, but the physics and animations are pretty rough, and there is a lot of amateur voice acting, with stilted delivery, mispronounced words, and so on. The camera controls are also odd and take some getting used to. In those ways it's not unlike playing a PS1-era platformer. All in all, not bad, exactly, but I think if I'd watched a few videos before buying it, my expectations would've been more in line with reality.
The Robot Rescue platformer in Playroom VR is a much better showcase for what a 3D platformer can be in VR. If Mervils had that degree of polish, and that camera, it would really be something special.