Indian Creek. Shooting Hevi13 3.5 - 2.25 - #7's I'm getting consistent 280's+ in the 10" at 40 yards with my 535 with a 20" barrel. I also have an SSX which put up similar numbers, but I liked the overall eveness of the IC better. I just got a Pure Gold choke for it this past Christmas, but I haven't shot it yet.
Here's a pattern with the IC .660 at 40 yards.