While using USB-C the monitor will repeatedly randomly go black for a second. HDMIs have no such problems. This breaks the usability of USBC for me. No response from the manufacture. Returning...I'd stick with the HDMI only version for now.Unless you have a basic keyboard and mouse plan to use the usb 2 connection, this breaks the keyboard's ability to be used for switching inputs. This is well documented by them, but is worth mentioning.Quickly switching between devices works great.It's functional and properly handles 4k@60. It's thin so looks nice mounted to the under side of my desk. I was disappointed it doesn't supply power through USB-C so I still need to plug in the laptop but that's not a huge problem.However, there is one frustrating issue: if you power off/sleep/disconnect and leave the USB-C slot active the attached monitor will never sleep (continually sleeps/wakes).I contacted the manufacturer and they are aware of the problem but have yet to provide a fix. If they can resolve the monitor sleep/wake issue I will bump up the rating. Otherwise I'm considering returning it.Unstable Video connection. Have to power cycle it all the time to have good video.I have this in my living room (not functioning as an actual computer KVM, really) running as a normal HDMI switch (half 4k, half 1080p) but I occasionally hook my laptop or desktop up and this makes it easy without having to dig around a bunch of cables behind my entertainment center. Later this spring when I get my security system hooked up, it'll run through this as well. I know it's technically for computers, but seeing as it only has single monitor support (1 HDMI out) and can't support dual displays, I thought this was better suited for living room duty. They have other models that are have multi-display outputs, this just isn't one of them. It comes with a nice selection of cables, but what would really be appreciated is a way to mount it. It has no mounting holes or anything, so if you plan on mounting this vs setting it on a desk, you'll have to be creative. Also comes with a very simple remote.Overall, it's a really nice single output KVM/ HDMI switch. It just needs a mounting system.I got this for a server rack that has a file server and two (2) CCTV camera servers, so I am only using three of the four ports. This means I am not using or testing port 1 which is the USB C port, and I am not passing through 4K video. So if my use case is far off from yours, this review may not be helpful.For my use, this is a great KVM and far better than the one it replaces. The three computers have dramatically different hardware and operating systems: a rack-mount Razberi server running Windows 7 Embedded, a Dell server, and an Asus gaming PC. The old UPS would lose connection to the Razberi server occasionally and the Asus PC all the time, but not this one. It has been rock solid and removed some headaches.My only complaints are the very skimpy manual (there’s a button for “Mouse Sensitivity Adjust” and the only explanation is “Press button to change the sensitivity of the mouse fast switching mode” which is not very helpful) and the lack of separate audio switching. I understand that it switches the HDMI audio and there is an analog audio output, but I could not get it to work reliably. Again, mine is a difficult use case, and your mileage may vary.A great device that can let you use up to 4 PCs with one monitor and one set of keyboard and mouse. It performs well in terms of transferring 4K video at 60 fps. I am personally not using multiple computers at the same time right now but I may need to so in the future. I think you should really get this KVM switch if you want to reduce the clutter on your desk and increase your productivity and speed. Controlling multiple computers with one monitor, keyboard and mice is a great convenience. I would recommend this KVM switch.My husband loves this KVM switch. He has a home lab set up with multiple computers. Before having this switch, he would have to constantly change the inputs on the monitor and have multiple sets of mouse and keyboards. The included cables were nice and he wished there were a way to mount the switch.I don’t need 4 computers accessible from one workstation at the moment, but it’s nice to know I have that capability. The usb c feature is a nice extra.This arrived without a manual.This product lasted less than 3 months before I started to have intermittent problems with it.One of the main input ports randomly died shortly over 2 months.Now the main connection to the monitor has died.I have no response from the vendor when I tried to contact him directly.I have had no response from the vendor through Amazon.