One of the best things about a Bradford White water heater is the hydrojet technology that they have used for years to reduce sediment build up in your tank. Sediment is the number one problem for most water heaters and can cause loss of energy as well as early tank failure.
The hydrojet technology is related to how the new water enters the tank. Most of the sediment that will accumulate around a water heater will build up at the bottom. This is almost always the case sense sediment is more dense than water. A layer of sediment at the bottom of the water heater will act as an insulator between the burner and the water. The more sediment you have in your tank the longer it will take to heat the water inside of it.
The hydrojet technology will blast the scale from the bottom of the tank every time the unit fills up. We have taken apart some older water heaters here in Kansas City. For a comparison we took apart 3 water heaters all in similar age. Not surprisingly we found that the Bradford White water heater had less sediment build up, especially on the bottom of the water heater.