We've been watching blue bloods on SKY HD. One episode jumped half way through (bad signal) so had to fire up Netflix US. When Netflix streamed in HD it was better quality than SKY HD.
A lot of stuff on Sky's own HD channels is surprisingly poor quality. I notice it with Arrow especially, the audio sounds extremely muddy and dull. Even had an episode a few weeks back where they were pushing all the dialogue (centre channel) through the rear channels instead. Utterly bizarre.