Ok I may be late to the subject but I too had heard conflicting info on run times and lumens for the Sten Prem 7. So I wrote them and here is their response in part These times by the way are for the SMALLER battery, the larger is double the figures show. Sten does sell a AA (6) power supply that with quality bats will equal these times, Lith Ion's a little better. Lumens are one thing, how they are dispersed is the really important thing
Here are approximate typical run times for an S7+ premium lamp:
Low: 10 days
Medium: 36 hours
High: 8 hours
Turbo: 2 hours (no thermal limiting) to 4 hours (thermal limiting)
300 lumens is a typical amount of the output under thermal limiting at
room temperature, though it can be lower in a very hot environment with no
air flow. 450 is a typical amount when first turned on (before thermal
limiting kicks in) or in a cold environment or with really good airflow.
We do plan to make a version of the battery with a molded plastic case
that will be as waterproof as the lamp.
Hope that clears things up . And yes the ability to change the frosted buttons on the Sten is something not found on most other lights, also Stens can be upgraded or rebuilt.....