On my sportbikes, it was pretty much a given that they ran a little rich out of the factory so I didn’t have any qualms just tossing the slip on there.
With the HD, I would think simply adding slipons would be ok because I’m not changing any air-flow/intake.
Though, I’ve read it’s still a good idea to get a fuel pack simply to make it run a little better/cooler.
I love the VH Big Radius exhaust, but man…I’m not sure I want to go the full-system route ($$). I think slip-ons, hi flow a/c, and fuel pack would be sufficient.
Now full systems on Sportbikes……
massive weight savings.