Switching from MH to T5?

[i have crabs]

i read a study somewhere and when they tested different mh lights and ballasts most used huge ammounts of energy when starting up and while running,electronic ballasts ran at proper levels but i dont think the starting up was any better,im thinking of buying a kill-a-watt so i can test things myself and know for shure instead of just guessing all the time.
i have no proof myself but i would shure assume any mh light system is gonna use a heck of alot more power than a t5 of similar wattage