I got a brand new Sky +HD box installed and before the day was out it had failed! First sign of trouble was that when I tried to watch a programme I had recorded the box switched itself off. I had to disconnect it from the power for two minutes before the box would function again. However the picture kept freezing when I was watching the recording, again requiring unplugging etc. Then later that day when I went to change channel, the box would not respond - again a power off. Finally I had programmed it to record a programme when I was out. On returning home it had not recorded and would not record when I tried a manual record. I tried unplugging it again, this time it would not come out of standby mode. I phoned Sky went through their troubleshooting (repeating the unplugging, then unplugging both power and Sat cable feeds and finally trying to force reboot it). Nothing worked. I had to wait 9 weeks from ordering to get the box, now I have another week to wait to get it replaced. The box I was supplied with was made by Amstrad (although I had been told that it would be Samsung, Thompson or Pace) - bad news as the only other Sky digibox that has ever failed on me was an Amstrad. The Pace boxes (both standard and Sky +) that I have had, have never given me any trouble.
During the few hours my Sky +HD box worked, I have to say I was underwhelmed by the improvement in the picture on my LG 37inch HD (1080P) LCD TV. Not sure if this is because HD is over rated or my TV does a better than average job of upscaling SD broadcasts.
I will give this one more go, but if my replacement box gives trouble I will be asking for my money back and reverting to my 100% reliable Pace Sky + box.