I'd like to share a cinema display between a mac pro and Powerbook. The DVI KVMs are so expensive. VGA KVMs are cheap. Would I get a much worse picture quality if I use a DVI to VGA adaptor on both computers and go with the VGA KVM? Since I don't want to spring for a DVI KVM, I guess my other option is to keep moving the display plug back and forth. Any other options out there?