I'm running the BD scoop....but I didn't buy the whole kit. Let me explain:
I'm runing a S&B with the top off (I want / need as much air as possible). The BD scoop tosses massive amounts of air into the engine bay just behind the S&B, which is nice. I also modded the factory air dam with three 1" holes (The BD kit has a new air dam that is a total B!TCH to install). I do NOT think it helped with my performance much, but I can tell you that my EGT's dropped about 30-50 degrees with the extra cold air tumbling in. If you look at BD's website you will see a new air dam that gets installed in the fender / fire wall on the pasenger side. With that you get air forced into the air box (But you may also get moisture and snow). The S&B box fits into the factory air dam at the bottom and also has the air cut out on the front side with the option of running open or plugged. My want / need for more air forces me to not only run the S&B unplugged, but without the clear lid. The scoop is forcing the cold air in right through the fender and frame cut out behind the S&B kit allowing a steady nice stream of cold air. With the holes I made in the factory dam, I'm also geeting extra cold air into the opening on the bottom of the S&B.....Win, Win, Win and no direct connection, so any moisture or snow will just fall down to the ground.
I think the scoop is great, but the BD kit is a B!tch to install, and I DO NOT like how the moisture has no place to go, but into the intake. I helped a friend install the whole BD kit on his truck and it was not fun. However, doing his install it gave me the idea of using their scoop along with my S&B and stock (Modded) air dam....It is a nice compliment to the S&B and would also work with the AFE's.
Again, I do not think there is any power increase involved, but I can assure you it helped lower my EGT's...and we all know how hot these trucks run with tunes.