They are not great. I had a USB-C adapter of theirs years ago. While the adapter itself worked pretty ok (besides only supporting 4k@30Hz), it was so badly shielded that it would reliably drop any Bluetooth or WiFi connection in its vicinity. I browsed through the Amazon reviews and it turned out that there were many people with the same issues (and also later USB-C adapters).

I know that USB-C can cause interference on Bluetooth/WiFi bands, but this was never an issue with properly shielded adapters.