I've never understood the term "soft release" for these things. "Button extension" would be a better description, as that's what most (perhaps all?) of them are. To that end, they increase the height of the button, allowing you to use the pad of your fore-finger rather than the tip. I haven't tried one, so can't comment on their effectiveness, but some people say they prefer the feel with them fitted. To me, it looks more like a trim thing than a practical improvement, but I'll reserve proper judgement until I actually try one