I bought 2 slip ons for my 08 to dyno test but got stopped by the weather Saturday. Basically they are the same design.
1 has a 2" core, the other a 2.5" core. Short of that and the length of each can, and the diameter of each can, the design is basically the same and probably holds true for most cans.
Why the manufacterers makes such long cans that most everyone cuts down is beyond me. The only advantage to a longer can would be more silencer material. But why that brand would care about the noise?
Basically all cans are the same design with a perforated tube of some size ranging from 2-3' wrapped in some type of silencing fiberglass with an external can over it. The extrnal can being SS, CF or Al. Purely asthetics there as well.
Short of that most slip ons are the same design, less cosmetics.
I dont think slip on designs are all that complex. Now when you get into the collectors and headers, very much so.
Hell there are some 08 owners just taking off their stock can and claiming it isn't much louder and makes more power with just the pre muffler. Heck of a slip on, for them, is no slip on at all.