I've been happy w/ my recent switch from KBB to the "new" Cowboy lump.
I get a few long cooks (butts/ribs @250-310) in the WSM from one load of lump w/o having to clean out the ash.
I (or, the WSM I should say) doesn't have the "inconsistent" burn problem some report w/ lump.
The minimal amount of ash is a great advantage w/ lump.
hopelessly, helplessly, happily addicted (to a shipload of Webers)