Also keep in mind that KVMs have latency - which is a BAD THING when you need to switch FAST.

I know it is not always possible but I encourage people who are looking to go for a true 5 box setup to do it right from the beginning - 17" or even 15" monitors are not THAT expensive nowadays. I still strongly suggest a hardware input solution and I would suggest avoiding KVMs. I don't use any except a single keyboard one to switch to rarely send text to all of the Zins at the same time.