If you are planning on regularly using the light (i.e. everyday) then go for 2 sets of a high power level batts (2500+), as you will get great capacity and can exchange them with a freshly charged pair every week or sooner without down time. Otherwise, if you plan on using it infrequently then I'd agree with Bomo and Badbeams and go with a hybrid like the Sanyo Eneloop. These type can hold a charge for a long time and be recharged.Delta said:How about all the different power levels they seem to offer? Go for the highest number?
Bomo said:One more thing - if you need to buy a charger, it would be best to invest in one that charges the cells individually. The chargers that you find typically in stores charge them in pairs.