In my experience with inhalers I can safely say that I have never been prescribed an inhaler that lasted as long as the manufacturer stated it should last. Easy one, albuterol never lasts as long as 4 hours, Foradil never lasted 12 (hence why prescribe twice a day) I could go on with all the 12 hour inhalers I have tried and it's the same. So with the new once a day inhalers I'm not sure I could trust them. Love to hear your experiences.