I got a couple of these in last week and put one on my LED analyzer gizmo (Any interest in a LED/Battery analyzer device?). They start out at around 2.45A/356 lumens (1/5 the advertised value) and drop to 1.4A/255 lumens by the time the battery (2300 mAh Sanyo) is empty after 90 minutes or so. Max temp reached was 55 degrees C after 20 minutes. Color temp was 6000K.
Ignore the numbers in the left hand and middle columns. The light was off at the time the screen dump was taken and are ambient background readings.