I had VMware buy me Belkin KVMs when I worked there. I've never had Windows/Mac OS X/Linux fail to recognize the keyboard/display when booted to a Belkin KVM.
I think only nice things about Belkin KVMs. Well, except for the (lack of) availability of their <2 PC to 2 DVI display> KVM, which I'd buy in a heartbeat if I ever see it again.
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Do a search for the $8 blue cube PS/2-to-USB converter. There is no substitute.