I've been an on-and-off fan of American Horror Story since it first debuted back in 2011. In my opinion, some seasons have been great, some meh, and some so resoundingly awful I couldn't get past the first couple episodes (I'm looking at you, 1984.)
Before I get into opining on Double Feature, let me just get my ratings for the previous seasons out of the way:
Good
Season 2: Asylum
Season 5: Hotel
Outstanding
Season 1: Murder House (simply because it was so new and different)
Season 3: Coven (Jessica Lange—and in fact the entire cast—chewed the scenery.)
Season 8: Apocalypse (Ditto from above.)
Meh
Season 4: Freak Show
Season 6: Roanoke (To be honest, I gave up on this one but eventually returned.)
Awful
Season 7: Cult
Season 9: 1984
(In the interest of transparency, I only made it 4 episodes into Season 7, and half that with Season 9; I just couldn't, and in fact 9 almost turned me off of the entire series.)
And that brings us to Season 11: Double Feature.
This year was a different format, cramming separate two stories into a single season. I suffered through the first story, Red Tide, just to get to Death Valley, the long-awaited alien/UFO story that fans have been clamoring for since Asylum.
Red Tide wasn't bad. It became engaging, although I found myself several times wishing they'd just wrap up the story and get to some sort of resolution.
I wouldn't put Area 51—the second half of Double Feature—in the outstanding category, but it was definitely entertaining. Murphy and Falchuck drew upon every bit of UFO legend that's out there, and somehow managed to weave it into a fun little thriller containing Easter eggs at almost every turn. Filming scenes in black and white that happened in the 50s thru the 70s was genius, giving the whole thing a sort of camp It Came From Outer Space vibe. Even the scenes filmed in the present were camp, drawing on even more UFO lore. My biggest complaint, however, was that it came to an abrupt end without any real resolution. Area 51 could've—and should've—been a full-length season in and of itself.
But that's just my opinion, so it probably is worth squat. Apparently everyone else hated the entire season.