Getting rounds on target fast is more a function of the shooter, than the choice of weapon. The 1911 does have a better trigger than most (all?), but this is not the complete answer to fast accurate shooting. You play a bigger role than the gun, in that capacity.
As for size choice, that depends on your intended use and/or carry method. Handle and shoot different sizes if possible. All my currently owned 1911's are Commander size (4 1/4" barrel). They simply feel right for me, and I can make them do what I want them to, better than a full size, or a compact.
As for size choice, that depends on your intended use and/or carry method. Handle and shoot different sizes if possible. All my currently owned 1911's are Commander size (4 1/4" barrel). They simply feel right for me, and I can make them do what I want them to, better than a full size, or a compact.