Earlier I wrote about selecting the Asus m.2 x16, a 4x NVME carrier, each with PCI-E x4. It arrived, i installed. The reason I chose this one is that a) my motherboard supports bifurcation, and b) my NVME cards were 22110 (with integral capacitors for write flush on power-loss). As you can see from the photo, i shorted the head-pad a bit because of the extra height of the capacitors.
If you are looking for a great deal on a lot of fast storage, check out the ebay listing. Or even some other online listings. @ $270/TB of fast NVME, how could you go wrong? Chuck your sata to the curb and join the revolution.