I added a DYNOJET USB III to my 2003 Deuce after adding the V&H 2 into 1s, it improved the throttle response, added a small amount of power, and killed the mileage (had a Terry Components feedback fuel tuner before). Combined city/hwy mileage: Big shots: 42-46 mpg with terry tuner, V&H 2 into 1s w/terry tuner: 48-51, V&H 2 into 1s w/USB III: 43-47 mpg. Now the plot thickens: My new to me 2003 CVO deuce has Thunder headers, and as purchased, no tuner of any sort: 46-50 mpg with poor throttle response, idle and poor power below 2000 rpm. Added the USB III from the other Deuce, didn't change any tuning yet, and picked up a major bunch of response, and power everywhere, smoothed the lope, and made the bike much more of a pleasure to drive. Prior to adding the USB III, as the temps fell here (Phoenix,AZ) from 105/110 to 80s/90s the bike felt slower and less responsive (seems to me from being lean). Now the question: my guess is that the CVO was leaner from the factory to pass smog with the bigger cam, and the T-Header made that condition worse, and that's why the USB III made a bigger difference. I can't wait to get the time to tune it! Comments? experiences? TIMINATOR