Have a set of new HD SE slip-on's ordered for my fatboy. Just discovered they are going to have CATS inside the mufflers. I owned a set of SE's in 2004, at that time they did not have CATS and were really nice sounding and torquey mufflers. Seems starting in 2006 (and all forward) they have CATS installed in them. Has anyone drilled out the CATS, either partially or completely, and if so what difference did it make? If it reduced back pressure, did it reduce torque? All information will be appreciated.