A recent paper, presented at NIP12 in San Antonio, described the relationship between heater power density and bubble nucleation. While the experimental results validated the model, it left an unanswered question, that is; what is the effect of power density and bubble nucleation on jetting performance? Increasing firing frequencies combined with more dense heater arrays act together to decrease the time available for pulsing individual heaters. This pushes power density upwards. However, thin film reliability issues often work in the opposite direction. Lower power density pulses, in general, permit longer heater lifetimes. Independent of these issues, there are jetting performance considerations. While heater lifetime effects are important, only the jetting performance issues are examined in this paper. In particular, this paper deals with droplet velocity and stability and their relationship to heater power density. Experimental data is presented along with simulation results. Bubble momentum is computed and used to explain the nonlinear velocity response to heater power density. Also, the spread of nucleation probability across the heater surface, is used to compute nucleation quality. The nucleation quality term has a direct relationship to the power density regime responsible for bubble instability induced droplet velocity variation.