willyrquick You'll find the text clear and crisp. Where the Goovis G2 displayed a slight pixelation on sharp lines and text, the Cinera Prime displays static photos/graphics, video and text beautifully. The 3D stills/video is the best experience I've had, including cinemas, 3D TVs, PSVR, etc. The main limitations with the Prime related to motion, which was probably down to hardware specifications - which should all be resolved on the new Edge.
I think the backers of the original headset will have collective nervous breakdowns if the vignetting isn't resolved. Those of us who beta-tested the original headset flagged this up before the headsets even shipped, but it was too late to make physical design changes by then. We've been going on and on about the vignetting for several years now, so I can't imagine that the Cinera team could possible overlook that issue again! 
The control pad is a handy gadget, whether or not you use it with Cinera. As you say, it isn't expensive, so I'm sure you'll be happy with it. I love that it can be recharged using a standard micro-USB plug, rather than the older mini-USB plugs that you rarely see nowadays.
I believe the problem with running Cinera as an Android device is that the hardware and drivers are designed to support whatever the current version of Android is at the time of development. As soon as the Android version changes, it becomes a losing battle to keep supporting the newer versions. This is true of all Android devices and represents an inherent problem in these devices that results in accelerated obsolescence of the device functionality.
Cinera is at its core a display device. Monitors rarely become obsolete due to operating system and software updates. They are limited by their resolution, colour and contrast ranges, refresh rate and connection sockets. Cinera Prime (and Edge Pro) can be plugged into external devices via the HDMI In, so in that sense it can remain future proof as a basic display device. The Cinera team wanted the Cinera headsets to be a self-contained media solution (which is fantastic in the shorter term for people who hate wires and only want to carry one gadget with them), and this is where I am slightly at odds with their design choice...
...the Cinera headsets cost a certain amount of money to make, so by adding the Android functionality (and the Dolby Digital earphones) the headset is going to either have to cost a lot more, or it will have to make compromises on the hardware. My personal view is that other competitor headsets out there, including the LUCI Immers made a smart decision by functioning ONLY as a display device, which you can connect to other devices via a USB-C connection (which can be adapted into an HDMI connection). This means that you can keep upgrading your phone handset and media gadgets (like the outstanding NVIDIA Shield), and headphones, etc, and the headset will continue to support all the latest software and formats via these external devices.
When you integrate all of these elements into the same device, it becomes impossible to stay abreast with all the new software and hardware developments. The design of the Cinera Edge forces you to use their integrated headphones instead of being able to swap them out for your own newer and more premium headphones - to me this is a design compromise they have made in order to use the headphones as a load-bearing support for the headset, so the weight isn't all on your nose or forehead (which becomes uncomfortable over time). If you don't buy the Edge Pro variant, you can't even connect to external devices using the HDMI connector.
The Goovis G2 is an example of a headset that sensibly follows a modular design, with the headset and the controller/media player provided as separate devices that can be upgraded independently.
All in all, despite my frustration with the above issues, the Cinera Prime was already overall a better option than these alternative headsets in terms of image quality and support for the native 3D blu-ray frame-packing format (I don't want to have to convert all my 3D blu-ray movies into Side-by-Side video files in order to watch them when Cinera can plug straight into my 3D blu-ray player and play the film straight off the disk).
The Edge will make the headset lighter and more comfortable and portable like these competitors, while retaining or improving on the strengths of the Prime model.