To have any kind of discussion on this matter you need to look beyond mere length. I am starting to realize that contour is more important than length when it comes to feel, how well the gun points and one's ability to make the hits. For example, my full lug 3" 625 is actually easier to shoot well than my 4" Mountain Gun. These very light barrel configurations are very difficult to shoot well and any change in your grip or shooting style will be greatly magnified. This will become clear when you are shooting on the clock and fractions of a second become very critical.
Thanks for all the replies! I`m trying to narrow down my choices for a revolver to use for IDPA type "action" shooting, so I need something that can point & shoot quickly.(.38 /.357)----------Pete