You know, you may have a point about the 8" rotor. I take it for granted that where I ride we have lots of mountains with some nice technical downhill trails where that 8" rotor really comes in handy. For where you live, it may be just added weight and not much of a performance benefit. I commented without taking your riding conditions into consideration. If you are happy with your ride the way it works now then I wouldn't change a thing.