I have the CMC-4's and have been very happy with them. Though I've had no personal experience with the CMC-8's, I've heard people on this board say that the 4's have a little better tonal quality. And the 4's are still quite small. Bass response in the 4's is not a problem. SPL handling is not a problem as long as you are using phantom power--they will brickwall quite easily with battery box power.