2016* graphics that was already only mid range the day it was launched. You’re welcome.Pros
BlackMagic eGPU: Buy, plug in, done
Others: Choices, cheaper, upgradable
Cons
BlackMagic: Can't upgrade, expensive for an early 2017 graphics card
Others: Time spent shopping for enclosure, shop for graphics card, plug in, hoping it's optimized for Apple (Metal)
The three things the BlackMagic box has going for it are design, noise levels (it's passively cooled), the ability to drive a Thunderbolt-based display from the eGPU. As far as I know, those last two are exclusive to BlackMagic.
Yeah, no other eGPU can handle an LG Ultrafine 5K display.
Here's an excellent review and teardown of the BlackMagic:
https://egpu.io/blackmagic-egpu-review-apples-ultrafine-curse/
One interesting thing noted in the teardown is that it speculates that a more powerful graphics card could be the endgame here if the initial BlackMagic offering is a success. The speculation is based on the power supply of the eGPU having greater capacity than is needed for a Radeon 580 Pro.