DHPP can also cover receivers that you own, which are otherwise out of warranty... so folks with older owned receivers can benefit.
What is and isn't covered on leased receivers has always been sketchy.
I know DHA (or DHPP) warranty covers shipping and provides some free or reduced cost service calls that otherwise cost you money. I had a 501 replaced last year, for instance, and they just shipped me a new (refurb) one free and a return tag to send the broken one back. If I had not been on that plan, it would have cost me to ship the unit back.
Unless you have credit card auto pay.