After wrapping up the third round, one fact became abundantly clear: none of the units from the first two rounds belong here. Apart from the Belkin we saw in round two, which deserves a thumbs-up for its MOV safety, the others are only marginally better than Sunbeam's solution from round one. The Diamond may also deserve somewhat of a mention for its shuttered outlets if that feature alone is worth more than $5 to you.
I suppose I am not going to surprise anyone by saying that, out of the nine units I looked into, APC's P74 wins overall. It can still be found for around $12, which is about the same (if not cheaper) than most other brands' nearest equivalent units lacking some of its features.
If the extra bells and whistles are not your thing, then Tripp-Lite and CyberPower also deserve honorable mentions if you can find them for cheaper than APC's first-place finisher.