Review on Perixx Periboard-522 Wired Trackball Mechanical Keyboard With 2.17 Inch Built-In Pointing And Scrolling Feature, US English Layout by Mike Larkin

I bought this keyboard to make it easier to work while my arm is in a sling after surgery. My overall impression is that it is solid and well-built with good tactile sensitivity. When I received the box it rattled, and on opening it discovered that four keys had come off in shipping. Not a good sign but I was able to snap them back into place (with one arm) and went ahead and installed it.There are three indicator LEDs above the trackball for NumLock, CapsLock and ScrollLock. Turns out the Caps Lock LED did not work on this one, which led to my returning it and I replaced it with the same model. This was through Walmart and not through the manufacturer.The replacement was fine out of the box and went right to work. After 1-2 days of working with it I discovered I was struggling to see some of the key overlays, and I realized this was because there is not enough contrast in the key labels: they are gray over black, instead of white over black. Also, as it turns out, this keyboard is not directly compatible with the IoGear GCS1462 KVM switch I use to flip my keyboard/monitors from my workstation to my laptop (I lose the keyboard hot-swap capability, so I have to switch by pressing a button on the KVM; a bit of a nuisance).I then returned that one citing the incompatibility with my KVM and ordered the backlit version (Periboard-322), which is another $50. I've never spent this much for a keyboard/trackball combo, but I use this professionally and need the built-in trackball for about 6 more weeks. The backlighting took care of the squinting issues, and I believe this will be a solid keyboard for many years.Note: I don't use any of the multimedia-key features, and I set the backlight effects to 'on' and 'white'. There are a lot of options for crazy wavelike and sweeping or raindrop effects that probably appeal to teen-agers (I guess).My 2-star ERGO rating is for the non-backlit version, which to me is hard to see under some lighting conditions because of the lack of contrast.PROS: - Solid feel, substantial weight - Excellent tactile feedback and response of keys without being too noisy - Simple clean installation with no associated drivers to installCONS: - Documentation is a bit light - there are two USB cables on the backlit version and no instructions as to which one to use; IT DOES MAKE A DIFFERENCE. - It would be nice if you could program the wheel button for something else, like double-click. Again, no documentation here. - Clustering/arrangement of Home,Delete, PgUp, PgDn and other control keys are a little odd and take somegetting used to, but this is not a show-stopper.Overall: unless/until something breaks, this is a solid keyboard for someone who uses a workstation in a coding environment (non-gaming) for 8 or so hours per day. It's a bit on the pricey side but there are not a lot of keyboard/trackball options out there, and that's what I need for now.**UPDATE 2/23/2020: Something actually did break: after about two weeks, the backlighting no longer works. Returning this keyboard, and dropped the rating accordingly. I am all done with this one.