Not sure on the A-B comparison but I bought a set of Klock SS slip ons for my Road Glide (95ci + cams) and they sound unique and great. They have a deep tone and quiet down at speed. I got the square cut and get positive comments on the look and the tone.
My bike already had the 95ci, cams, intake and download done with SE slip ons when I made the swap to Klock SS slip ons so I had no problems. I doubt you need a downlaod or fuelpack if you anen't changing the intake. Call Klock; great guys to deal with.