I really like all three, but have a real appreciation for 5.5" lately, making it a slight favorite. I have found the 5.5" is still packable in a normal belt holster. In favor of the 7.5" is that my aging eyes can focus quicker on the front sight, and hold that focus better. In slight favor of 4.75" is that the less muzzle-heavy balance is easier on my right wrist, but then I shoot an SAA best as a lefty. 5.5" seems to have no real drawbacks in handling and carrying, so it is a default favorite, and the look is growing on me.