What are advantages and disadvantages of scientific experiments?

The tremendous scientific advances that have taken place in the past few centuries are largely the result of the successful use of experiments. We have seen, therefore, that experiment is an extremely powerful tool with which to investigate any natural phenomenon. The main disadvantage to scientific experiments is that they can be very expensive. The recent experiment to confirm the existence of the Higgs particle cost about a billion dollars. It is not entirely clear to me whether this information is really worth what it cost to obtain it. Still, the physicists are happy.