I haven't flown the ElectriStar yet but I expect the flight times to be between 10-15 minutes depending upon the amount of aerobatics.

I realized my mistake above in the power level for using the two NiMH packs and corrected the numbers. Since the wattmeter was only measuring the voltage of one battery, the power is doubled due to the second battery in series. Therefore, the power level looks fine with the stock NiMH packs although the plane still weighs a pound more than when using a LiPo pack.