Well, growing up I was a BIG fan of the Simpsons. I had tape (VHS) after tape of episodes recorded as was always watching them.
However, right about the time this season aired, I really stopped watching the new episodes. The quality of the episodes writing and over all comedic value really dropped off. Yea, there are a few really good classic episodes, and some funny moments here and there, but NOTHING close to the quality of the first 12 seasons (even 12 wasn't as good).
Some say the show had been on so long it had nowhere left to go. Some say they sacrificed quality to try to add more crudeness and edgyness to compete with South Park. Some of that may be true, but I agree with others that say the new Exec. Producer, Al Gene, began to drive the show into the ground.
If you are a die hard fan, it's worth picking up. I ripped them to my HDD and deleted the bad ones. To me, there are only 8 episodes of "The Simpsons" in season 13.