The SESE website tells me that these are the sunflowers to grow if you are growing them to eat their seeds, "big seeds" "great for munching".
And I just learned the neatest thing about sunflowers from wikipedia. Their heads, the part we think of as the flower, are actually 1000-2000 individual flowers joined together by a receptacle base. Here is some more on that, "What is usually called the "flower" on a mature sunflower is actually a "flower head" (also known as a "composite flower") of numerous florets, (small flowers) crowded together. The outer petal-bearing florets are the sterile ray florets and can be yellow, red, orange, or other colors. The florets inside the circular head are called disc florets, which mature into seeds."