I haven't seen Homeland but Downton is such complete tosh.
Don't get me wrong...I watch and enjoy Downton...it looks marvelous, its well acted, and anything with Maggie Smith in it can't be all bad, but its still tosh.
For a start, Highclear Castle plainly isn't an Abbey.
For a house of that size, it would have needed at least 50 servants, not the few that we see.
The familiarity between staff and Upstairs is just not believable.
Finally, the script and storyline is risable. Are we really supposed to believe that somebody was so badly wounded in the WW1, that he was in effect a paraplegiac, and then he made a complete miracle recovery !
And the chuaffeur married the daughter of the Duke !
And have you noticed how incredibly clean all the working class parts of the village are...no horse poo...anywhere ?
But, as I said, I still watch it, even if its only for Maggies eyebrows !