Should you believe a show that is created to bust myths over a show that peddles psudoscience? That's up to you. I have never seen "In Search of...?" so I don't know their methodology when investigating these phenomenon. It is possible they went about the process in a very scientific matter with large sample sizes and control groups etc...
I do know that myth busters at least tries to be scientific in their approach to these kind of issues. I guess the main problem the the experiment they did would be sample size, but other than that it seemed to be pretty solid.
I'm curious why you would consider "In search of...?" more reliable. What is your reasoning?
If you view something as being stupid, it is not worth investigation?
Well I wouldn't spend time on it, but people can waste their time however they want. My issue is when taxpayer money gets spent on dumb ideas. Once again I would refer you to the baloney detection kit I have linked you twice.