I've used a number of inexpensive KVM switches in the past, starting way back with the mechanical ones. Until now, I've always found them to be quirky. Often they don't handle higher video resolutions well, or the mouse and keyboard don't reconnect properly on the first try.
Recently we've been buying D-Link KVM-221 2-port USB KVM switches for about $50. I can say this is the first time I've never had any hiccups at all in implementation. It even includes the cables.