Koblenz.... rather than chase after velocity or energy, these days ammo makers are designing bullets to perform fairly comparably across weights and calibers... for example... the top defense loads in 9, 40, and 45 all give fairly similar expansion characteristics and penetration... close enough to not be overly concerned that any one is significantly "better" than another... if well placed, repeatedly, RAPIDLY... the top defense loads in 9, 40, and 45 will all give roughly comparable results. I feel it's best to choose loads which one can hit accurately with, repeatedly, and at a high rate of follow-up speed rather than seeking out "the one" which has the highest velocity or the most energy. In .40 caliber, the 180 gr. is relatively easier to shoot with rapdi follow-up shots, easy to control, and it's quite effective when placed where they need to go, therefore, I prefer that bullet weight in .40 caliber. Again, bullet placement, repeatedly, and very rapidly stops fights quickly... given 9mm +P, .40 cal. or .45 acp, the particular caliber or bullet weight is of relatively little concern.