It involves some outside the box thinking, but here's an option.
A Surefire LX2 paired with a Malkoff E2/Scout, E2 Super/Scout, E2T/Scout, or E2 Super Throw/Scout gives an operation like what is desired. Instead of low and high modes, what's delivered are more like medium and high modes.
A light press on the switch delivers momentary "medium" and mashing on the switch delivers momentary high. Tightening the tailcap activates constant medium, and tightening the tailcap further activates constant high.
The more voltage that he head receives, the brighter the medium mode. I find a 16650 to provide a better medium output than two CR123s, but both options are safe.
It's not exactly an inexpensive package, but the LX2 head can likely be sold to recoup some of the cost.
I personally consider the clip for the HDS Rotary to be too far from ideal for it to be worth serious consideration....to me. A 325 lumen Clicky with a Prometheus clip is close, but I've had issues with the HDS switch being confused if I press it a bit too long while attempting to turn it off, and it just switches (or stays) on Preset A instead of turning off. Not good if you really need the light off RIGHT NOW.
