I've had this dock (
https://eshop.macsales.com/shop/owc-thunderbolt-dock) for months now. Using it with my M1 MacBook Air.
Connected to it are powered speakers, a Logitech Brio 4K webcam, Logitech RF mouse dongle, USB-C to DisplayPort cable (connected to a 4K Dell monitor), Apple TB3 to TB2 adapter (connected to a TB2 SSD) and a Belkin USB-C ethernet adapter.
I've had no problems with the dock at all
with the exception of the built-in ethernet port. For some reason, it seems to disconnect itself from the computer every so often. A Belkin USB-C to ethernet adapter plugged in to one of the dock's USB-C/TB3 ports has been rock solid and bypasses the dock's own ethernet adapter. There's been a couple updates to Big Sur since, so maybe it was something Apple fixed, but my setup is solid as-is, so I have no need to mess with it.