Since I carry a .40, I guess I have to say my favorite is a .40. Not sure I would use the essence of favoritism other than practicality. I'm not going to load 9mm's in it.
With that said, I choose Speer Gold Dot JHP in 180 gr for it. Reason: I did my research, I took into account cost per round, and quality from this manufacturer. For those interested in the ballistics of this round, here it is:
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