Do KVM Switchs Have Lag Problems?

[vanwazltoff]

i have been thinking about getting a KVM switch so i can control multiple computers with one mouse, keyboard and monitor. the potential problem that comes to mind is lag between all of the components, i would like to use my sidewinder x4 and rat5 but i think that would cause lag issues when gaming, i dont plan on using the KVM for my main display but i would probably use it for my secondary or my b!tch display [old dell monitor that i use on clients computers, dont ask why i call it that haha]. if there is a potential for lag i would rather just get a 2 port KVM and use my wireless keyboard instead.