In my 15 years with DirecTV I've had two receivers crap out and three dish issues addressed. All were covered 100% by the Protection Plan. Yet I have been ridiculed by some in the past for wasting my money. Where I live when the service tech's foot hits your driveway as he's getting out of his truck the cost is $85.00!
Service call used to be $79.00, has been $49.00 now for a few years.
By extending your 15 years at todays pricing, you will pay $1,080.00 for the plan. Replacing 2 leased receivers in that time would cost a maximum of $40.00 for shipping. If a service call is made and the problem is the receiver, they will credit any charges that are made. That leaves $1,020.00 for the 3 dish "issues". At current hardware pricing, you could replace the entire Dish assembly, including LNB and any standard multiswitch (if applicable) for less than $200.
Bottom line is that it is a "protection plan" and is designed to make money for DirecTV not save money for customers. If it were "worth it" for everyone, they wouldn't offer it.
Are there cases where it is a good insurance policy to protect a much higher investment (owned receivers, high dollar SWM setups, etc...)? Sure, but for the largest majority of Dish/cables/receivers households, it is not a good value. Much better to save the money and pay as you go. In most cases, they will credit a service charge or offer some sort of programming credit to offset.
I would never ridicule anyone for having it, only offer up the math and have them make their own decision. From a personal perspective, the more people that have it the better, it helps keep the service costs down for the rest of us.