Your ECM will compensate the Air Fuel Ratio to factory specs just fine for slip ons, even a stage 1 filter. A dyno tune without something that can change/adjust the ECM's AFR is a waste of your money. You will get a nice 8"X10" chart for your dollars.
Are you saying I can add a stage 1 air filter with my reinharts slipons and don't need to do a download or spend money on a fueler?