Whats good about getting a master of science in finance?
Finance is harder than some subjects and easier than others. If you are an undergraduate business major with some math and statistics classes you should be fine. Finance involves a good amount of math, especially in understanding the theory behind many of the equations and calculations.
As for careers, really depends on what you want to do, but it will most likely be in the field of finance. You could work for a large company in their finance department, work for a bank approving loans and performing credit analysis, you could do valuation work at a Big 4 accounting firm or work in investment banking. If you are more interested in helping people with their finances you could work in wealth management. Really up to you.