I did one Ester change at my dealer and it cost me $92. That's why I only did it once.
Nissan "recommends" the Ester oil, but personally I think it's a snake oil sale. There are other oils that have Ester in them (Mobil 1 and others) that are a whole lot cheaper than the $14/qt that my dealer charged.
If you drive a gazillion miles and they actually cover it for 36 months without a mileage limit, it's probably a good deal. If not, I don't know that I'd waste the money. The best way to tell is figure out what all services they do along with the prices of said services, then compare to the contract.
Trust me, they sell those to make money, but if you drive a lot, you'll beat 'em.