I too notice the shorter burn times (although still quite long IMHO) with Royal Oak Briquettes and other "ridged" briquettes. Honestly with the 30 gallon drum as opposed to 55 anything I cook seems to get cooked.
I would encourage you to try Kingsford Competition. Smells good and burns good. It's just hard to find.
Blackstone 2-Burner, Primo Oval XL, Tiernan SOB,
The Pit Barrel Cooker, Big Green Egg-Mini, 4 Webers, Lodge Sportsman, Cobb Cooker