I only listened to a little bit of the video. The Duncans immediately sounded squishier than the others, the Aftermath was obviously much crunchier and tighter - it's "squeaky" tight, a little more open sounding, and has a more tense, angry midrange, which squares with my experience. I suppose Keith didn't change the patch he was playing through, which is good for comparison but doesn't show you what can be done to settle in with each individual pickup; EQing before the amp, fiddling with compression, etc.
My money is on the Warpig being more detailed sounding than the non-BKP options. (I was immediately blown away after replacing an alnico EMG.) I suppose you should get the Pig if you like to chug and you like the impact of the picking sound and a thick tone, or get the Aftermath if you want more brightness and a tenser, tighter crunch. The Warpig (at least the ceramic one I have) is not at all loose sounding, but the Aftermath has this immediate, dry sound that plays and feels differently. Either would be good depending on your needs.