I chose the DD TT box because of less aggressive timing, hence a bit quieter running. The Box does not make as much HP, but I felt it would be better for the life of the truck. I used to run it with a set of Bullydog Stage 2 injectors, but had too much smoke. Now that I am running 275RV's, I chose the most agressive setting on the DD box & have minimal smoke. With my DTT TC & VB this is a very nice set up. When I can afford a Piers Turbo & a 4", I will go back to the Stage 2 injectors, The stock HY-35 on my truck just does not cut it EGT wise for anything more than the 275's. I would buy DD again.