I have the Romisen and think it's a good light so far. I tested the run time on a pair of Sanyo 2700 batteries and got almost 4 hours.
I was with a group on tour in Goliad, Texas and after supper in town we rode back to camp in the dark without street lights and I felt comfortable with this light.
I am still amazed at the amount of light it puts out.
Two is a good idea. One up close and one pointed a little farther down the road and as a spare.