summer day/night monitor and ordering an extra camera

i notice their are different types of cameras you can order some are cheaper then others....does it make a differrence which one u order??? i have the silver camera and i was looking to order an extra one but the blue one which is 30 dollars cheaper...do u think it would work>??? its also says day/night///thanks

Message edited 9/9/2009 8:57:28 PM.