To reaffirm what I was getting at is just look at the scores at the Side by Side tournaments that are shot with vintage side by sides. I had a friend year before last shoot a 48 out of 50 using a 1880 Boss 20 bore hammer gun at the Southern Side by Side event. I would think that is pretty damn good shooting.
Now I suppose if you are a dedicated Sporting Clays shooter and want to use a side by side to shoot events then maybe a 8 plus pound gun may be fine. Just thinking about re-sale value as well. A lot easier to sell a field gun than one with a adjustable comb, high ventilated rib, choke tubes sticking out of the front.
I once shot Helice at my Gun Club and there was a guy there who was shooting a Model 21. It had extended tubes and the barrels were ported. Now that was a terrible thing to look at.
But what I see on a weekly basis is a light field side by side shooting 7/8 ounce loads in 7 1/2 will break all the targets as long as you do the job of putting the barrels in the right place.

Mike Proctor