I've had it for about a week and no problems. The lag that people keep referring to is literally less than 5 seconds. I'm not sure under what circumstances an 'instant' switch is required, but I can easily run on 3 separate devices with a short delay between switches. Absolutely no performance is lost. Incidentally, the delay mainly affects the screen switching, keyboard and mouse react almost without delay. I think other reviewers should consider the cost and be more realistic about the short delay. My only complaint is the lack of a software switch - in the 90's and early 2000's KVM switches could be toggled with a hotkey like Alt + ScrollLock or something. I couldn't find anything similar in the manual and it doesn't respond to typical hotkeys, hence 1 star for the lack of this feature.
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