Final Followup
After calling Dish on 11/29 about my failing 622, the refurbished 622 arrived on 12/2, only 3 days later, so I was quite happy. Especially since I didn't have to pay anything.
I was hoping for a 722, which I understand some people have received, but what I received was a used 622 with scratches and a little gummy residue on the top, probably from a sticker.
Anyway, it took about an hour to set it up, get it activated, and download the program guide. I wish there had been a way to import all my timers and channel lockouts, but, all in all, not a bad experience, and everyone with whom I spoke at Dish was helpful and pleasant.
Richard