I've been very happy with my tesmart dual DP 4 port KVM. The only limitation I have is that it's only usb 2 host controller, so a lot of higher speed devices like some webcams can't get switched using it.
LAlso if you need Apple products in the mix, you have to use two physical usb3 cables from the mac just to distinguish the two display channels because apple hates MST for reasons (another reason to hate their arbitrary bs).
I have a TESmart and the other problem is that the autoswitch doesn't work with custom keyboards, as the KVM needs to emulate the HID and doesn't like a keyboard that shows as a hub.
LAlso if you need Apple products in the mix, you have to use two physical usb3 cables from the mac just to distinguish the two display channels because apple hates MST for reasons (another reason to hate their arbitrary bs).