I have the Dragula 2 into 1 on mine. I really love the sound from 2000-3000 rpm. The rest of the rpm range is just cool as heck! Idle sounds nice like a Harley ought to.
The performance gains were considerable from stock using my seat of the pants dyno. When the weather gets down to 60's I'll have it dyno'd again to compare to my stock run.
I'm using a Power Vision tuner and their Autotune wide band O2 sensor module.
Jamie at FuelMoto was helpful on the tuner and Frank at Dragula had the exhaust in stock when I needed it.
Using the AutoTune Module and doing data runs and adjustments was really easy.
What I really like about the Power Vision is the monitoring you can do of almost everything the ECM is looking at.
Engine temp, fuel economy, Lambda, and a whole slue of other elements.