Husqvarna FS450 Supermoto Race Bike, and we have also used them on our personal builds as well as customer builds with great success. Not only do they look much better than the stock calipers, they give you much better brake performance in terms of bite and feel. These are a great compromise of cost vs. performance without stepping up to billet racing calipers which are exponentially more expensive.
OEM Supermoto Calipers feature a 4x34mm piston design, by reducing the piston diameter to 4x30mm it means you will be pushing the same amount of fluid from the master cylinder to move 4 smaller objects. The result? More power from your brakes while reducing lever effort.