I have cooked a lot of wally world briskets which are generally "choice" grade. Pick through them and find one that bends easily and looks evenly cut on the flat. It will be good to smoke. The idea of smoking a brisket is to take an otherwise tough piece of meat and cook it tender.
There is a lot of different things going on in smoking a brisket until it is tender and juicy, too much to go into here. There are lots of methods out there to get a good tender and juicy outcome. Just do what works best for you and you will be successful. Read all you can from other cooks and apply what you think will work with your needs and your smoker. Good Luck!
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