In concept, the SF momentary/twist tailcaps sound great on paper. What I've found after trying a few of them is that the feel "clunky" when depressing the button for momentary, requiring quite a bit of force to activate and keep from flickering. I've also found that getting the tailcap adjusted just right is critical. In comparison the McClicky switch has a much better momentary feel, and it takes a long push to click it constant-on.

I've also modified the McClicky to be momentary only, resulting in smooth flicker-free feel and ease of activation. Of course the downside is that constant-on is no longer functional, which may (or may not) be an issue depending on how you use the light.

For dual-output I still very much prefer a bezel switch vs. tailcap control ("gas pedal" or multiple switch activations). I'm also finding the automatic step-down after 10 seconds of the Malkoff Bodyguard heads quite useful. In short, I want tailcap switch activation to work seamlessly with gross motor control of the thumb, which neither the SF gas-pedal or the classic control of output via multiple activations of the tailcap switch can provide.

My current hand-held that is dedicated to self-defense purposes uses the modified (momentary only) McClicky and the Malkoff Bodyguard head. I can gently activate or mash down on the switch to activate, and the light reliably turns off by simply removing the thumb from the switch - no fine motor control needed. If for some reason I want reduced output, I simply hold the switch until it automatically steps-down after 10 seconds (a quick blip of the switch resets the timer). For a SD light, I find this arrangement superior to any other I have tried.