Finally took the plunge and decided that, although my 2013 Paperwhite is still going strong, I'd treat myself to a new ebook device. Having seen both the Forma and the Oasis in John Lewis, I decided the bigger screen was worth having.
Long story short, the Forma has managed to find my wifi network only once, as part of the initial setup process. Once it downloaded an update, it hasn't been able to find my wireless network again, despite multiple restarts of the router and the Forma.
In the end, I gave up and used the Kobo Desktop to set up using a USB cable which seemed like a return to the dark ages - I remember having to use USB with my 2009 Sony PRS-505.
I managed to purchase a book but the device wouldn't eject either from the Kobo Desktop app or using the USB in Windows 10 so I shut down the computer to be on the safe side. At least my book had arrived on the device.
Alas, the screen is terrible - the brighter strip on the grip side of the screen is really distracting. Setting brightness to 30% and cranking natural light up to 100% makes it bearable, but I didn't pay £240 for a reader that's bearable.
I think I'm going to return it