I compared my allegedly 5mw one to a friends alleged 30mw pointer on the weekend at our 100hrs event.
Admittedly mine lives in my pocket to keep it warm and his was mounted on a finder but I couldn't notice any difference. Both worked well enough and sadly both illuminated the clouds that were over us at the time.
I find that temperature is the biggest killer with mine and it needs to be warm to give a nice beam.