Personally I have tried so many through the years and for the past ten I always go back to royal oak hardwood lump. You can get it very hot. It does not have the endurance of kingsford briquettes. It is one of the best in my book because of the high heat factor, and a 15 lb bag is 6 bucks at wally world.
I know you are looking for an answer on the difference of the 2 kingsford, but I do walk by it to get my royal oak.
I use KBB (Blue Bag) for long, low, slow smokes and either lump or a lump/KBB mix for hot shorter smokes. KBB burns at a very even steady rate which in my WSM means I can get 22+ hrs. out of a 20 lb. bag.
I actually asked someone from Kingsford about the new "Professional" bags today. He told me it's the same as the Kingsford Competition brand, just a new name and package. I'm a fan, as they do burn longer, hotter and cleaner than the regular Blue Bag.
I bet they changed the name and look because "Competition" and the price turned some consumers off.
I use KBB (the original) to start my offset stick burner but i like RO lump for my WSM. The reason i use KBB to start my stick burner because I can get 4-19# bags for like 34 dollars. so when i just using it to light my fire i want to be cheap as possible also i can use it with my kettle for a hamburger or whatever.
I haven't really noticed it since im just using that 2/3 of a chimney of kbb. i started using it because i saw a video on youtube with a guy saying that RO and KBB starts up about the same so he saves money with kbb but uses RO for other things. i will try the RO (which i love in the WSM) and see if i find a difference. thanks for the tip!