I would keep the barrels original. You have to reload. These dispersor wads from BPI are great.
http://www.ballisticproducts.com/Dis...tinfo/072DX20/
Spreaders do work. Keep your chokes original for the long shots and use spreaders for upland game, close shots on the clays course, and skeet.
Below are patterns from a full choke Remington Model 17 with full choke from 21 yards which is the center post distance in skeet.
20 gauge load with Federal hull, primer, Long Shot Powder.