I probably have not shot enough different 9mm handguns to say for sure and certainly haven't owned them all but considering all factors I'd have to put the Browning Hi-Power at the top with the CZ-75 running hard on its heels. The P7 is slick, slick, slick but just different enough for me not to pick it. Having listed some classics, I have to add that the Ruger P95 is very high on my list. The Timex of handguns. The Jeep of pistols. Does everything it is supposed to do without fuss, complaint, drama, or question. But the Hi-Power stands alone at the top of the hill. Oops, you asked why...combination of looks, history, all-steel construction, balance, length of barrel, enough capacity, single-action trigger, feel in the hand, slimness of slide, etc. YMMV