Update:
I finally got a decent meter and I measured the power. After this thing warms up it simply refuses to drop below 500mw. This reading was taken after leaving the laser on for around 7 minutes. The peak on the meter was remaining from an earlier test at approximately 3 minutes.
With fresh batteries the average is around 550-560mw. When running it off the power supply it averages 530mw and can be left on for 15+ minutes without any overheating.
586mw Peak!