External storage does not have to be slow, as the OWC Mercury Helios 3 PCIe Thunderbolt 3 external drive demonstrates.  The TB3 connection is capable of up to 40Gbps, assuming you have the proper connection, which will keep a drive such as the the Kingston DC1000 NVMe SSD very busy.  In The SSD Reviews testing, they saw the data transfer cap out at 2.8GB/s read and between 2.5-2.7GB/s write, which makes this perfect for HD video or for manipulating large media files. The enclosure will set you back about $200, the cost of the PCIe SSD you put inside it is a choice for you to make.

"The trick…is Thunderbolt 3 and the external devices companies envision to solve this speed and data storage problem. This is where the OWC Mercury helios 3 PCIe Thunderbolt 3 Expansion Chassis comes in."

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