KingoftheRoad doing a complete stage 1 you can usually expect to see a 8-10 hp gain over stock, more then with just mufflers, for sure. I have to disagree with TQ on HD downloads (but that returns the ECU to the lean condition you started with) the HD stage 1 download is built in Milwaukee by their engineering department to richen the fuel mixture to the right level for running the stage 1 on your Harley and if you have a problem, Harley is there standing behind it, where as if you install a TFI, your on your own, well the forum is very good at helping out, I've heard nothing but good on this forum about the TFI fueler and if you enjoy playing with tuning yourself it can be the way to go, but Harley made a fuler of their own in the past and I don't see it being offered anymore, maybe my staff patch is showing but if Harley stopped selling them it tells me there's a reason, and we all know how much Harley likes to make money by selling things, anythings. TQ you know I respect you and it troubles me a little having to disagreeing with you, but life sure would be boring if we all thought the same. KingoftheRoad I recommend doing the research and you decide what is best for you. I'm a old dog and set in my ways, but I'm not blind ether, I know my way is not "always" the only or best way.