A few years ago, I would only use lights with forward clickies and momentary on. I was a single mode kind of guy. The Shiningbeam L-Mini II changed that for me. Why? Because the beauty of the reverse clicky in this implementation meant that the light was dead simple to use, click on, click off, with a different mode available if and only if you wanted it, by lightly depressing the switch when on.
The forward clicky with momentary is in my experience the preferred clicky when you want/need momentary and/or are using a single mode light. It would also be the preferred clicky when using a multimode light which changes modes using a mechanism other than the clicky switch itself, i.e. with a head twist or separate switch on the body of the light. For me:
One mode light?
Forward clicky with momentary
Multimode light with mode changing through tailcap switch?
Reverse clicky
Multimode light with mode changing through mechanism other than tailcap switch?
Forward clicky with momentary
...and that's how I like my lights!