As an old time meat cutter- brisket is one of the pieces of beef that is just as tough on a prime as a standard grade. It's in an area where the fat can be heavy around it, which is good for the taste and moisture but low value for eating or serving. The flavor is going to come from seasoning - the time you put into that and smoke job you do. I suppose a prime grade could have a little better flavor, but it would have to be a real competition to go much extra cost. What you see at Cosco/Sams/Walmart, may not be much different than what you can get at a local meat market. Same with ribs and the rougher cuts that my folks use to give to the hired hands cause they only wanted the best parts. It was those poor folks who figured out how cook this stuff so it was good to eat. Once we figured it out, we got a few of those ribs and brisket cuts, but ask them what to season it with. Heard it all- apple cider- vinegar- brown sugar and spices- there's a million ideas. I like a lot of em and have the gut to prove it.
