The GP is a nicer gun, but as far as CCW goes, the SP is a much better option. It is lighter, typically shorter and thinner. All of these combine to make it a gun that you can carry easily every day regardless of season.
A GP, while it can be done, is more difficult to carry daily.
Both are accurate with the GP getting the nod as a range / home defense gun and then SP as the CCW gun.
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