The L2 on low and the X5T are roughly equivalent, I got both. The beams are different, the L2 throws a bit furter, the X5T is uneven due to the 5 Nichias.
In any case, the power consuption of the L2 on low is about the half of the X5T, and the runtime, at constant brightness, is the double. The X5T has a longer "tail" since it is purely passive.
Anthony