It's free on YouTube. It's pretty good, and they managed to not use any of the riffs from the mst3k version, so it's almost like a whole different movie (except, of course, that it's still Manos.)
Part of the reason I like the black & white movies are because I saw them first on Saturday afternoons when I was a kid. Seeing them get riffed reminds me of being 10 or 11 and making fun of them with my friends.
Ok, here's a dilemma: I'm saving Manos for Halloween, but which Manos? Manos mst3k, or Manos rifftrax? Not both - I don't think I'm capable of watching that twice in one night, no matter who's riffing it.