Review on SIIG Thunderbolt 3 Dock: Dual 4K HDMI Display & USB 3.0, 40 Gbps Docking Station for Mac/Windows by Mark Lowery

I have two 4k monitors that support 60 fps on my computer but this box does NOT support them both with the promised FPS. When both monitors are connected to the hub, one gets stuck at 30Hz and the other at 60Hz. This is definitely a limitation of the hub; If I just connect one monitor to the hub and the other directly to the computer I get two 4k@60hz. Perhaps this limitation only applies to the extended Mac OS desktop, but I doubt most home/office users will use a mirrored setup. There were also a few instances where I had to unplug and plug my computer back in to use anything connected to the hub. Once I had to restart the whole computer.