Also, Apple Care + is transferrable when you sell your iPad. At least for now ... there is talk that changes are coming, coverages will follow the person, not the devices.
I had the iPad 1, then sold it when the iPad 2 came out. I still have the iPad 2 and will be upgrading to the Air. For both the iPad 1 and iPad 2 I purchased Applecare and never used it. This time, I will opt out.
Don't forget that some credit cards automatically double the manufacturer's warranty for free and provide accidental damage coverage as well. Something to consider...why pay extra when you don't have to?
On the other hand, you can never have too much insurance.