Pivot Bikes use a dw link which changes the ratios. This bike uses a single pivot at the seatstay. There is that useless pivot at the hanger, i'd prefer a flexible chainstay.
Pivot has a switch chip, that allows two different geometry but both bikes use a 4 pivot horst linkage system, allows for the rear wheel to come back when you hit big rocks. They have also worked hard with the leverage ratio to even out an air spring shck allowing the initial travel to be softer.
By flexible pivots do you mean like in the picture, There great if you're on a super light cycle cross, down a country lane, but if your hammering through a rock garden or just cased a big jump a little extra travel is nice. A bit like comparing a mars bar to a can of coke, both have their place.
