Depends on the forward voltage of the LED. A low Vf (J) may run full power depending on the efficiency of the converter. Haven't studied the converter in the Gladius yet but if it uses a synchronous type switcher, a J voltage bin Lux III should get decent runtime at full power. If you're bold, you can get yourself a TWOJ (or better) Lux III and modify the LED in the Gladius.