The other guy is correct Hoosier. A person can add NFL ST Max for the 2013 season now, if they wish. They also offered it early last year, for customers who want to pay it off early, instead of waiting to the fall. As stated though, the base (non-Max) NFL ST is not yet available to add. You can go to Directv.com/nfl and you'll see it's available to add. If you click on activate now while logged out, you'll even see it specifically states for the 2013 season.
In answer to the OP, I use to have comcast (still do for internet), and I love my DTV. HD is great, and if you like sports, then DTV is the leader in that department. Good luck in your choice!
I asked to add it and was denied, so good luck with all this.