I have a 7" Marshall monitor that I use with 2 Canon cameras. Adding a field monitor has made it easier for the people I work with to see whats going on. When I'm by myself I only use it when I've a static set up and I'm not in a rush, or just want to show a more impressive set-up. The most essential use I have for the monitor is in conjunction with a lanc controller when using a jib crane. So, IMHO, if you use a crane or regularly have people watching over your shoulder, get a monitor. If you don't, the fascination with them soon yields to set-up expediency.
