I'm going to pass the first two thirds and proclaim, Miku is the awesomest foil for Mitsuba. I cannot remember a pair of antagonists so great since Yomi and Tomo. It is different, of course. The balance is strictly maintained (in the pool episode, Miku had the upper hand, in this one she was hoisted on her own petard). I think I like it more than Yomi always getting a short stick. Plus, the action of the two brings out the best in animators and seiyuu.
The other two segments were somewhat underwhelming by comparison. I mean Matsuoka is crazy, I get it already. The Papa bonded with Futaba nicely, which was fine, I suppose, just not quite at the level of Lucky Star 22.
BTW, remember the numbers? It turned out that the numbers are the birth order, as Hitoha considers herself a younger sister to Futaba. So, the names are backwards.
UPDATE: The grumpy animeblogger with a heart of stone takes an opposing view:
The fourth [segment] was just another little game of one-upsmanship between Miku and Mitsuba and picked up a little bit of steam towards the end, but the two of them don’t have all that much comic chemistry together. They’re both basically the exact same character, with slightly less sadism on one end, and they really only have a single joke about their claims of maturity backfiring through their segments. Repeating that joke ad nauseum does not make it funnier.