Still there are some disadvantages that I hope the Pimax 8k solves:
* No physical IPD adjustment with the Pimax 4k, which makes my eyes tired and make me feel uncomfortable after 15 minutes of playing. Since the Pimax 8k has 2 display's it should be easy to make a physical adjustment system
* No 4k input mode for the Pimax 4k. Pimax said they're woking on native 2x4k input support for the Pimax 8k, although we'd need next generation video cards to actually drive them at 4k native resolution, it still would be great to have it
* The Pimax 4k has quite low FoV, I'm really looking forward to the FoV of the 8k
* Tracking: like you said Nolo sucks, really looking forward to the Pimax laser tracking system for the 8k
* Ergonomics: the Pimax 4k is not very suitable for Caucasian faces, hoping they improve that with the 8k.
* Colours and brightness: if the 8k indeed has OLED panels this will be MUCH better
* Eye damage: If the 8k indeed has OLED panels, then they will be much safer for your eyes since OLED transmits 3x less blue light.
* Ghosting: Needless to say it will be MUCH better with OLED panels.
So yeah I'm really looking forward to the 8k, if it really has 2x4k OLED panels then this is going to rock the VR world like nothing we've seen before !
It's still unsure though at this moment if the Pimax 8k will have 2x4k OLED panels at introduction .. @xunshu is holding the cards close to her chest