I have an SLP with an 18-inch barrel and a 28-inch barrel that I use for trap. Great gun, needs at least 250 rounds to break-in / seat the bolt. I have the Briley INV-SK choke in a diffusion constriction for the 18-inch barrel which provides good buckshot control and is rifled for slugs. 18-inch barrel is Invector style choke tubes while the the 28-inch barrel is Invector Plus. I have a complete set of Rhino Chokes for the 28-inch barrel.
You might also want to consider sending it to SureCycle. Have them do a reliability tune-up, new magazine spring and follower, and put the SureCycle recoil system in it. The SureCycle system will decrease felt recoil by at least 20 percent while improving the cycle time. They also modify the gas pistons by removing the spring and installing a solid ring. With the SureCycle mod, the heavy gas piston will cycle 1-oz loads and, of course, everything heavier so I don't ever change gas pistons unless I want to shoot 7/8-ounce trap loads.
I've had mine done, and prior to the SureCycle system using 1-1/8 oz #8 birdshot loads (as a standard) - it would put 5 hulls in the air simultaneously. With the SureCycle it will put 6 in the air. A lot of the 3-gun folks with SLP's have had their guns done by SRM Performance (SureCycle).
I prefer mine to a Benelli as it has far less recoil, and is easier to control on follow up shots. Have shot my SLP against a Benelli and wouldn't trade my SLP for the Benelli.