I purchased that exact drive for a boot drive and am extremely pleased with it. It's fast, reliable (good reputation vs. M.2 drives anyway), and for a single drive, pretty quick. It supports UEFI bios and booting, so that's nice too.
Is it the best solution for video editing? Possibly, if your media and projects are really short (small). Personally, I feel that for desktop workstations RAID 0 arrays using multiple SATA SSDs provide larger and more cost effective drive space vs. any of the newer NVME PCIe and M.2 single drive solutions. And for my work flow, 400GB would be way too small. I've had excellent luck with 2x, 4x, and 8x RAID 0 arrays using Intel (X25, s3610, s3700, 750) and Crucial (C300, M550) SSDs for over 5 years now. I have not personally used any Samsung Pro drives in my RAID 0 arrays, but from what I've heard/read about those drives, I would feel very comfortable RAID'ing those too.
Sidebar: for anyone limited to running on a laptop, ignore this workstation advice; for laptops, M.2 drives rock! (where you can't fit so many drives)
M.2 drives are as reliable as their SSD package counterparts. The only real difference is the controller if one. Beyond that they almost always use the same type of NAND the SSD package use. The NVMe drives are great for OS but so small or expensive for the larger sizes that raided SSD's are a far better purchase for media and cache. The speed of 2 Samsung 850 Pro in raid 0 for example gives around 1GB/s on average and a larger volume size. PCI-E slots are normally better used for GPU's, I/O cards, and controller cards. I would suggest using the sata ports for any media drives versus PCI-E slots.