Replacing all those 20-50 [W] EL bulbs and with it's 7 [W] does better and for longer time.
Images added Apr. 20, 2013 (did't notice there was such ability):
First pic is of it in the protective transparent ball, in the bathroom, to show it in off condition.
Second pic is with it in on condition.
The bathroom in which these photos were taken is 2M X 2.30 M in size.
They were taken in day time and automatic flash on the Cellular camera.