Robby gave CM and I the cliff notes version of an Appleseed. We did it in a few hours. A real seed takes a full day or 2 with numerous drills. He basically taught us the positions and we moved on. I was happy with the score. All shooting was done with a sling as a stabilizer.
Yes, a rifle sling is a MUST. I like the cloth type, kinda like belt material because you can wrap it around your hand pretty well.