I've just updated from 10.0.10586.494 to 10.0.14393.67 by converting from SAMSUNG GT-I8750 to NOKIA RM-1109 Lumia 640 (some info says RM-1109 could refer to both 3G and LTE flavors of 640, not XL one).
I've used RootTool to change registry settings in HKLM\SYSTEM\Platform\DeviceTargetingInfo:
from
PhoneManyfacturer = SAMSUNG
PhoneManufacturerModelName = GT-I8750
PhoneModelName = GT-I8750
to
PhoneManufacturer = NOKIA
PhoneManufacturerModelName = RM-1109
PhoneModelName = Lumia 640
So far here's what I'd like to note:
? Quick launch buttons and app icons in the app list have become larger like if screen resolution has decreased (same experience as when mimicking Lumia 950 XL).
? Unlike with mimicking Microsoft Lumia 950 XL, third party camera apps, Camera360 Sight and Microsoft Office Lens, work as desired; at least there's no black screen I saw when I launched them on fake 950 XL.
? Battery drain it's still a huge showstopper: 70% loss of capacity in 1 hr of using the phone with Cellular data ON. No WiFi, no music, couple of minutes in WhatsApp, 50-55 minutes of opened Edge. Just this forum, no other tabs opened.
? Edge is plain disappointment and PITA.
Say at the moment I can't manage to select text in this edit box where I am typing my post message.
Surprisingly, there are still lots of small features that make me happy stayin on Windows 10 vs Windows 8.1.