I had to reset one box three times and another twice before I could get them to work. Anyone else who got theirs backup finding the channel changes to be slow.
My HR21 updated last week with latest firmware. It seemed to be running slow, but at least it worked. My HR20 got the update last night. I did a RBR, hit the guide button, told me the firmware had been updated then went to a black screen and locked again. Hmmmm..... Hope this is resolved soon or I'll be getting phone calls at work from my wife and kids.
Since all of the guide data is flushed, and has to be reloaded. I would expect it to be slow for at least the next 24 hours.