Frustrating.

From what I have seen and although the statements have been that a SD835 chip will be required, the fact is all the demo videos have had Windows 10 running on a SD820... the same chip in an X3.

I wouldn't count it out just yet :)

- Hopeful Windows Fan

That means nothing. DeviceID probably doesn't even have the 835.
 
I think if they make it available for the phones at all, they will test the performance on various models and then set up upgrade paths based on the results. It does not make sense to install it if the phone runs like a dog after.