I would say do what you want to, never hurts to reduce recoil. I got the XS skeet but I ordered it with the adjustable comb because most stocks are to low for me. Some are also too short. The last couple years I've been shooting an older 12ga 1100 field, added a half inch to the length and a 1/8" kickeze pad on the comb to raise it, shoots very well and kicks less than the 20ga XS. (I gave 300.00 for the 1100) you know what an XS costs. The XS would cock the hammers reliably so I sent it to Browning for repair while it was out I played around with the 1100 gun and I've yet to go back to the O/U gun. Don't be afraid to try different things. I recently bought an 1187 trap gun, very gentle on your shoulder. So far, I can't hit with it but I haven't given up on it yet.
I hope it works out. The 870 is ok except for doubles.