Almost all the Chinese headsets are Google Cardboard-style devices (technically, while most of them are compatible with Google Cardboard, they are technically off-spec since to be certified, the devices shouldn't have headstraps... [1])

There are one or two AIO units like the ANTVR, but they are just as terrible.

Soon people will be able to easily access/compare the high-end sets vs the Cardboard-class stuff and this sort of confusion will seem silly (in the way that comparing like a $0 Tracphone to a Samsung S7 or Apple iPhone 6S)

So here's a list of some of the differences:

* Tracking: None of the off-brand devices have positional tracking (the Oculus Rift, HTC Vive, and Sony PSVR do). This is pretty key to having a good VR user experience (both for immersion and comfort), the GearVR actually does ok for rotational-only w/ high res IMUs and good head & neck model, but positional is much better. Almost all the Chinese knockoff devices use the phone's IMU which not only suffers from drift, but typically sample at 100/125Hz vs 1000Hz - in practice (and you can compare it running a GearVR in native mode vs in Cardboard Mode w/ a disabler), the tracking is pretty terrible and makes me sick in minutes. There's of course no sensor fusion since there are no sensors to fuse and there's lots of additional path-latency that's optimized out of the better systems

* Display/Rendering: Currently, high quality VR requires low persistence OLED displays. GearVR (new Samsung flagships have modified tcon firmware to support this), PSVR, Vive, and Rift are the only guys with this built in. The higher the refresh, the better - GearVR is at 60Hz (ugh city, especially on the periphery and w/ bright colors), Vive and Rift are at 90Hz, PSVR is 90Hz or 120Hz. Motion-to-Photon (M2P) latency should be <20ms. Cardboard devices might be lucky to get to around 50ms to 100ms (Android also has poorly synced audio on top of video). The optimization for latency is non-trivial and you can find out lots and lots on this topic watching various technical talks on YouTube if you'd like. The other big thing that none of the knockoffs have is any sort of timewarp/reprojection.

* Lenses: at best you'll get off-the-shelf biconvex, but more commonly terrible planoconvex lenses. The high end headsets are actually using custom multi-element aspheric fresnel (Rift) or dual-fresnel (Vive) lenses (not sure what the PSVR is using, but it looked quite good, better than the Vive). None of these are particularly cheap and the lenses themselves cost more than the entire BOM of any of the Chinese knockoffs. These are better in just about every way you want to measure a lens - abberation, sweet spot, contrast, sharpness, fov. The Rift and Vive also have two physically separate panels that allow for physical IPD adjustment.

* Ergonomics - weigh distribution, straps, facial interfaces are all generally what you would expect from a $5-20 piece of cardboard/low-cost plastic. The Rift gets bonus points for designing for comfort

* Software - Another huge difference is in the SDKs/APIs available - the high-end sets have proprietary APIs that provide HRTF 3D audio, tuned rendering pipelines (working directly w/ GPU vendors, etc), better engine plugins, and dev relations/first-party content. They also have stores that allow third party developers to get paid. You'll just never see the majority of the experiences created for any of the high-end headsets on the Chinese knockoffs.

tldr: right now, you get what you pay for.

[1] https://static.googleusercontent.com/media/www.google.com/en...