I have shot both rounds a lot over the years. I also reload for 38 S&W. I found that the Fiocchi 38 S&W FMJ has quite a bit more get up them the lead ball Remington you can buy off the shelf.

I have carried my Terrier and my Walther PPK/s. Both are comfortable, but I actually shoot the Terrier better then the Walther.

So, as has already been mentioned, carry the one you shoot best and hope you never have to use it.