Yes they are very pricey aren't they, and a pain in the button to install.
Unfortunately, I did mine on a laptop and it's a bit different in a desktop, but I can share some info.
When you go uefi mode it basically block the bios from reading any drive but the nvme ssd.
Second you should not have any errors when switching back once it's switch on it will be like starting a cpu without any hdd.
Three every install is different I installed a fresh windows 10 on my ssd so the only thing used the cloning software with was to use the disk partition ability to format my drive into gpt.
Windows 10 doesn't need drivers so I didn't go through that hassle.
It took me 4 hours to actually get the install to work but once it did it was done in minutes. Oh and windows create a 500mb partition for recovery, just FYI. Sorry if I didn't cover everything if you got any more questions just ask and I'll answer whatever I can
Edit
I know this isn't a guide because my install is for a laptop so I can't help with the process but I can give you some tips if your bios doesn't see the drive when you switch modes you cloning software should have a way to make a uefi Bootable disk so you can flash your nvme to to gpt because u don't wanna run legacy , windows wont boot off of legacy installs.
Good luck
No problem. I've thought it over. As long as I can clone the SSD successfully as it is now to an M.2 NVMe card, I can wait on this.
I had to go through a few hoops, but I shrunk my Win 7 logical volume "C:" to 250GB and used the unallocated space to install the free Win 10 download successfully.
I'm still troubleshooting some minor hardware quirks, mostly pertaining to recognition of USB devices and especially an external SATA DVDRW-burner. I am sure I set that port to "hot-plug" in the BIOS.
But it's done. GPT partitions, dual-boot Win 7 and Win 10 on a 480GB SP550 SSD, all booting in "Windows UEFI Mode."
I'm going to take time to think about either waiting for a good 1TB M.2/NVMe, buying something like the Plextor, buying the Intel 600P . . . or just waiting.
As long as I back up at major milestones like the one I've reached, it could be a question of spending the < $200 to get the 512GB Intel drive and knowing I'll want to replace it later, or just . . . . waiting.
I have a cheaper strategy for the interim. I need to move my PrimoCache license from the system I am selling to a friend, and put it on this Skylake box. Then find the 120 GB SSD I bought some months ago, install that, and then see if I have some spare 1TB WD Blue drive around here.
This could be shaping up to be a great system. It looks pretty good so far.
I would think every Z170 owner would go through some learning process with this, unless they've been busy with Haswell in recent years.