I use a Lang 60. The heat under the baffle cooks the meat from the bottom and then the top as the hot air/smoke travels back toward the stack. I have a full width upper pull out grate so there are two levels of cooking. The bottom left (towards the trailer hitch) runs a bit cooler than the area to the right (firebox end) because the heat comes out of the firebox and onto the baffle. This works for me as the left is used for ribs/butts and the right for chicken. I can run 225 on the left lower and 275 on the right upper.
FEC100 - Lang 60 - WSM - Traeger