Well, I think it can take non-rechargeable Lithiums just fine though I haven't gone through an entire set yet. Looking at those runtime charts, it looks like if you want regulation, the Newbeam is the way to go. Sure the NiteIze starts off brighter, but after about a half hour, the Opalec is brighter and stays so for the next nine + hours and if you use the light often, it will probably pay for itself vs Lithium cells in about 5 battery changes.