JAYCL600

Just curious if you guys notice that on the bi-turbo CL600's have small front calipers as compared to the SL600 which has the big 8-piston calipers similar to the 65/55 vehicles. Are the calipers a direct swap? Are the rotors different size? Hopefully someone can shed some light on this because the parts to switch over are cheaper than a Brembo upgrade. thanks