Most service calibers are going to perform to nearly the same standard. High energy rounds such as the 10mm, 357 Sig and the various magnums "may" give you a significant advantage but may not depending one your proficiency with them.
The real answer is if you want to carry a 9mm carry a 9mm, but master the weapon. You must be able to run it without conscious thought. You must be able to make decisive hits while moving off the X. It takes training and practice to do that.
I have 3 Glocks that I use, 2 came in 40 and one in 357 Sig. I convert the 27 and 23 to 9mm and 357 Sig as it suits my needs and carry the 357 Sig. For a gun I am going to want in a fight its a hi-cap. You may feel fine with 5, but not I.
Your tactics and proficiency are more important than caliber or platform. Every situation is different, that is another compromise and your carry system must encompass as many variables as possible to ensure success.
My rifle and pistol are tools, I am the weapon.