Seems a bit overkill unless you're tracking your car. Not to mention kit wont be a direct bolt on. What yr saab and model do you have? If it's not an aero you will need to modify dust shields. You would need to machine the kits rotor center to fit over the saab wheel hub and you will need the 20mm caliper mounting bushings mentioned throughout this thread.
Correct me if I'm wrong, but isn't both the factory cobalt ss brembos and the ones listed in the zzp big brake kit both 4 piston? Is the main benifit going from the stock cobalt size rotor of 12.4" to 14.5"?