As a 70 year old aero mechanical engineer that became a commercial pilot when radios were tuned by coffee grinder crank knobs, I marvel at what electronics are today and understand little past ohms law. I do understand that I have been enjoying not smoking analogs and vaping for more than three years and in the last year since I discovered the the LM2596 this enjoyment has multiplied ten fold. They do everything I need and the less soldering with these old fingers, and eyes, the better. Of the many I have, I have only burned one up and that was oxidizing a SS wick that was shorted. If battery efficiency is the only advantage, I don't need that for PT with 12V source. Now if the better models give more flavor or more vaper, I may be interested in building one. I do understand that those that live electronics want to build the best, but for me the LM2596 is the best.