It's diminishing returns though isnt it? I noticed a nice difference between 16, 21 and 72 engagment points, I'm not sure I'd be so impressed going to 120 point. All three firms you name, or the first two at least, have strong, reliable mechanisms. This one has a couple of fairly dubious points, and needs to be made with greater accuracy, so it's going to be expensive. Doesnt really strike me as worth changing to this mechanism for the small benefits.