If you're looking for income investments, then it's awfully hard to argue with the massive distribution payments from LINN Energy (OTC:LINEQ) (UNKNOWN:LNCO.DL), Breitburn Energy Partners (OTC:BBEPQ), and Vanguard Natural Resources (OTC:VNRSQ). Thing is, though, income investments need both a decent yield and a level of certainty that it will keep that distribution going for many years to come. Other than being high-yielding investments, they are also all master limited partnerships, which means you need to look beyond just the operations to see how these companies will stand the test of time.

There are three key elements to look at when it comes to LINN, Breitburn, and Vanguard; distribution coverage ratio, weighted average cost of capital, and its investment grade rating. Find out what these three measures mean for the future of these companies and which company stacks up the best on these measures by tuning into the video below.