In my experience, the Beginner Box has been a great way to bring first-time RPGers into the fold. It throws the players right into the action and lays out the rules as they progress through the first session. Veteran players might feel stuck on the rails, but it can still serve as a good tutorial. The maps and character tokens are nice, if you like to use those in your games.
 
Also, you'll probably want to order 2 packs of dice anyway, so this will supply you with one of them.