Forget round count. 5 shots vs 15 shots.
Forget carry condition, recoil, difference in how they shoot.
Also forget "shot placement is most important" of course it is, but for this case. You have 5 rounds of either type, you can put them anywhere you want on the perp. All five rounds in the head or all 5 in the chest, which round do you prefer?
5 rounds of .38+P (Gold Dots or Hydroshocks) or 5 rounds of 9mm +P (Gold Dots, Golden Saber, Critical Defense etc.)
Type of carry gun does not matter, 5 rounds to 5 rounds.
Which do you think is the better round? .38 or 9mm?