I suppose it really depends on your workflow, but what has worked for me, as someone who works on both Mac and PC daily, is that I use a software mouse/keyboard sharing utility (Sharemouse) that allows me to connect one of my laptops to my dock and display, and share a mouse/keyboard/clipboard between the two. My second laptop is positioned off to one side and acts as an additional monitor of sorts. If I need to switch which device has access to the big screen, I simply move the cable. For me this is not a common switch so it works well. Better than involving additional hardware.