The store bought kanger coils last me about a week to a month each with cleaning and re-wicking done every 2 days or so. I have1, DIY Protank coil that was wound in September, it is the best coil I have ever wound and see 2-3 days a week of use. But in general I'd say coils last about a month and wicks 3-6 tank of fluid. FWIW I build my Kanger coils as 30awg verticle coils and use walmart cheap cotton for wick.