Short answer - I boost mine as needed, but return it to calibrated level after use (I do not like it boosted for music listening).
Longer answer (in case anybody finds it useful) - When I calibrate, I do it so that the center is at 0dB and offset all other channels relative to that. That way I can easily note if my center is boosted and by how much rather than by trying to remember what the calibrated offset is. I have shortcuts on my Harmony remote for center up and down in all of my programmed activities which is extremely useful.
