They are the same type as fitted to my 600 hornet only brembo instead of nissin, they worked well but got worse due to rubber brake lines, I guess the s2r will still come with braided lines?
The calipers were mounted on some sort of sliding pin system so the caliper moved as you braked because the pistons only come from the outside pad and the pulls the inside pad in, i think? looks more complex and more parts involved to mount caliper to and the sliders needed regular cleaning/greasing in winter to
they don't look so good either