about the same with using the wheel brakes. when you slow down you eventually have to get going againDieseltech's right on all other accounts, but:
If you are not accustomed to an EB, it can hurt your millage. Some folks don't understand throttle control and therefore will needlessly apply the break. Also, the converter is always locked putting more drag on the driveline.
Coasting allows you to travel without burning the additional fuel. The EB does not allow you to coast, and therefore you use more fuel when you accelerate back to speed.