It works well for connecting two monitors to one device (or vice versa). I have it to connect my computer to two monitors.

It plays 4K/60Hz without any issues. In QHD it also works OK at 60Hz, but if I set it to 75Hz it randomly disconnects once every 2-3 hours, and at 100Hz it doesn't work at all.

It works satisfactorily. I have connected a laptop and a PC to the same monitor and it switches between the two after approximately 5-10 seconds. At first, sometimes I had to unplug and plug back in the cable of one monitor to the switch for the switch to "catch", but gradually this stopped happening.