From what I know about automatic transmissions, using the power button is actually _better_ than not having it on.

Take, for instance, a Cadillac with all the extras. The transmission in those cars intentionally slip a lot when going between gears to smooth out the transition. This can cause additional wear on the clutches, which is probably compensated for with better materials, synthetic fluids/additives, and better cooling, but it's still clutch-riding.

The power mode increases the pressure constants and RPM thresholds in the PCM, which is usually a good thing all around. The actual "punch" between gears is healthier for the transmission than having a smooth shift.

The power button is one of the things I really loved to see on the VX, once I learned what it was. On one of my past vehicles, I had to do all kinds of mods to the inside of the transmission to replicate the effect (boring out holes in the valve body, upgraded servos, upgraded pump, etc.). If I must tolerate an automatic transmission, it should jump, not slide between gears.