Scroll down about half the page to see the Stinger. Under internal I/O it lists M.2 Key E. The other photos show what is included, other than the board, inside the box and you can see the adapter, and the physical keying of the M.2 slot.
And yes, this looks like 2242.
I'm looking to reduce the number of power cables in my current build, and get away from the 2.5/3.5 storage solutions, and AHCI. Some cables are required, of course, and my still desiring ODDs will add some more, but throwing an NVMe drive on a 4 lane M.2 would be good for me. (Hence why I said the Stinger doesn't work for me)[/quotemsg]
You're right that is frustrating, I wonder why they chose such a form factor. ADATA's solutions aren't bad but if you don't want to use the PCI-e port for your SSD your choices seem pretty limited here. I would rather use an 850 Pro over SATA than any 2242 option available right now.