wondering how often I would need it's application.
I have been part of green screen productions for a long time. Let me tell you they never are a good substitute for just shooting it live, in my opinion. If you are going to use a green screen for location replacement you better have an awesome Special FX department backing you up for it to look real. For some people it does work, I just have yet to see it work worth while and for all the setup. Just be careful, if done improperly it can really suck a viewer right out of the mood.