The third movie this season, Lords of the Deep, is a mediocre Roger Corman knockoff of The Abyss, pretty unremarkable save for Bradford Dillman's extremely hammy acting. The fourth, Charles Band's The Day Time Ended, is a real mess. It's like the effects team came up with a bunch of unrelated sequences they wanted to animate, so they threw together a script about a time warp causing random unrelated things to happen to a family in the desert. Even Batman v Superman had a more coherent plot.
Episode 5, Killer Fish, was pretty good -- not the movie (a run-of-the-mill piranha disaster movie with Lee Majors and a cast of moderately well-known late-'70s actors), but the episode around it. Surprisingly, they're making increasing use of M. Waverly and Growler, the Jonah-built robots that were used last season as just one-shot gag characters to illustrate Crow and Servo's hostility toward adding new bots and screwing up the dynamic. Those two started out the season making brief cameos in the theater and providing musical accompaniment for one or two host segments, but by episode 5, they feel like proper (albeit secondary) members of the ensemble, getting recurring bits in the theater and being part of a rather fun host segment. They also provide the music (and Gypsy the vocals, mostly) for something I've rarely seen before, a full song performed in the theater during the movie.
EDIT: Okay, I finished the marathon. The last film is Ator, the Fighting Eagle, the prequel to the second Ator movie which opened MST3K season 3 under the home-video title Cave Dwellers. A pretty ordinary Italian sword-and-sandal flick and Conan the Barbarian knockoff, but with a couple of nice host segments and a better ending segment than the first season had.
By the way, I noticed in the end credits that Mythbusters' Tory Belleci is one of the model-builders for the miniature sequences.