After replacing the stock header pipe containing the catalytic converter with a Jackpot stainless steel head pipe, adding a high-flow air cleaner and installing the FuelMoto Dynojet Power Vision tuner, I replaced the stock mufflers with Jackpot Carbon Fiber-Billet slip-ons. They sound great with a deep non-metallic rumble, but they are too loud for my spouse to tolerate for 8-10 hours on trips. I took them off, re-installed the stock mufflers and will sell the Jackpots in the spring, hoping to find a quieter, deep-rumble slip-on.