And if you want fast SSD Thunderbolt 2 drives (internal PCIe/NVMe not SATA), these would be top of my list....
http://www.sonnettech.com/product/le...lashdrive.html
... if you can still find them anywhere.
The Sonnet Fusion Thunderbolt 3 and Samsung X5 SSDs are faster but Thunderbolt 3 only, won't work on Thunderbolt 2.