Got a question. I just swapped out my HR10-250 for a HR23-700 and was wondering about the HD feed on HDNEt and HBO. I got these in the 70s on my Tivo, now I see they are mirrored at various places. Are the feeds at 501, and 3xx MPEG 4? Just wondering if I can save space by recording from these vs. the channels in the 70s.