In my experience, lighter is always better. When you fire a gun in "action" (not practice, but real stress) you will not notice ANY recoil. You are much more likely to carry a 15oz gun than a 24oz gun due to the comfort. The one time you say "That thing is a little uncomfortable, I don't need it today" may be YOUR last day.
Carry something comfortable, no matter what it is.
(I prefer a loaded blonde!)