I played with my setup last night for the 1st time since the HD upgrade last year. I have the HR22 box. I didn't see much of a time-delay difference with Native on or off and with 1080i only selected. But maybe it all has to do with what type of display one has and how fast it talks to/from the DTV box. I have a Panny 50: Plasma "Viera" model.
What I did see, after changing the settings as some have here, is that (it appears to me) there's a "trade-off" if one gains channel-response time. Without Native on, and selecting only 1080i for your display, when you tune to a non-HD channel, ie, TCM, the Native function won't auto-select the 4:3 mode on your display so the movie/show on TCM will be left in "full" 16/9 mode and will be stretced. Since I"m one of those "view contenct in their OAR" guys", I'll probably stay with the Native/on mode for now.
What I did see, after changing the settings as some have here, is that (it appears to me) there's a "trade-off" if one gains channel-response time. Without Native on, and selecting only 1080i for your display, when you tune to a non-HD channel, ie, TCM, the Native function won't auto-select the 4:3 mode on your display so the movie/show on TCM will be left in "full" 16/9 mode and will be stretced. Since I"m one of those "view contenct in their OAR" guys", I'll probably stay with the Native/on mode for now.