I only had very minimal growth with the Brava System, but this was mainly down to me not being able to keep up with the strict regime. I think at my longest point, I managed about 6 weeks of 11 hours per night, but I found it so difficult to sleep on my back all the time and found I wasn't getting enough sleep. Many times I would roll onto my side in my sleep and then wake to find I had lost the suction.
I did get the tingling and tightening after Brava use, but this was after using it for a few weeks. With the NB, we are in control of how much suction we use, whereas with the Brava, I felt it wasn't pulling tight enough, not stretching the breast tissue enough, so maybe that is why we are experiencing the tightening, tingling etc so soon because we control the suction so get results faster.
Ann how long have you been using the NB?