Tom: Please quit using those big words like "ergonomic". I had to go look it up. The off/on switch is recessed at the back so you can sit the unit upright like a candle if desired. I own two Surefires and one Streamlight that I don't even use since I found the Main Beam. Frankly, no comparison. In all honesty the off/on switch on the shaft of my Streamlight was one of the things I didn't like. I was constantly rotating the shaft in the dark trying to find the button. The rear switch is always in the same place. And I can turn it on/off with one hand, eyes closed, in about one second flat. Also, PM22.. no, you don't have to cycle through different settings to turn it off. If you turn it onto the lower setting then soft-touch the button to increase the lumens, when you turn it off it automatically goes back to the original lower, energy saving setting. The high technology and functions of this little light blow me away. Thanks for your interest. BW