Originally Posted by
rms13
I'd rather have a matching groupset. I have 6800 and mine stop on a dime even with carbon clinchers
The new Shimano 9000/6800/5800 brakes are SLR-EV. They recommend that those calipers only be used within that generation of Shimano levers that are matched to them.
Of course, they'll kinda work with any lever, but it may not be with the optimum power and controllability.
I like Shimano, but SRAM and Campy also make equally great groups. I would say stick within a manufacturer and generation for best results. Mix and match usually results in some type of frustration. SRAM and Shimano cassettes are the rare exception, they are very interchangeable.