Last week, Zack's Equity Research rated Energy Transfer Partners (ETP) a "strong buy," citing the partnership's increased diversity, both operationally and geographically. Units of the master limited partnership have had an abysmal year, and sit virtually flat from January's price. Is something broken at ETP?

In order to start figuring that out, the slideshow below compares five key metrics at Energy Transfer Partners to not only its large-cap peers Enterprise Products Partners (EPD 1.08%) and Kinder Morgan Energy Partners (NYSE: KMP), but its Energy Transfer cousins Sunoco Logistics Partners (NYSE: SXL) and Regency Energy Partners (NYSE: RGP) as well.