Royal Oak is high on my list of do not use. Several years ago, I was getting a lot of non-burnables in Royal Oak lump, including better than a half lb. chunk of what I suspect was clinker (kiln lining.) I sent in a message to Royal Oak, and the reply I got back was more or less "too bad, so sad." Tl;dr: I got tired of paying for something that didn't burn.
I generally use B+B in my grill and Cowboy in my smoker. Cowboy tends to spark, and that just does not matter in my smoker. B+B doesn't spark, but for the last couple of years, seems to take a bit more incentives to start up in a chimney starter. Rockwood is also awfully good, but at $35/20 lb bag, is sort of out of my price range.