There really isn't a "passive" hdmi switch. They all have to be active due to HDMI license issues. The Monoprice switchers are hit-and-miss. Sometimes they work and sometimes they get finicky or just don't work at all. The Gefen switches are more expensive, but they are very good. The 6x2 matrix switches is the cheapest one with more than 4 inputs (it has 6), but it is $823:
http://www.gefen.com/kvm/gtb-hd4k2k-642.jsp?prod_id=11453
The Gefen 4x1 is $462.
They are expensive. The cheaper ones may work, but unknown. Sometimes you can get deals on ebay.