another vote for Maple Leaf. It is the best. When I go to Canada, I bring back several bags - available at Rona, a sort of Canadian Home Depot.
I just discovered GFS (Gordon Food Service) lump. I've read it's food service quality Royal Oak. Lots of big chunks. Lots.
Cowboy is junk. I wouldn't use it to line a cat box.
Primo Oval XL, Medium Big Green Egg, New Braunfels Off set, Weber SJ UDS, BRK