The result looks amazingly good. It probably helps that the shows are from the same studio so the style of the artwork matches. It’s interesting to see which Madoka character they think corresponds to each Sasami-san character.
I find myself wishing that this were the real OP–which means, I guess, that I liked Madoka better than Sasami-san. But that may be unfair. I’m not sure, when I first watched it, that I liked Madoka all that much after seeing only 4 episodes. My view of Madoka in hindsight is inevitably colored by the revelation of Episode 10 and the stunning final episode.
If Director Akiyuki Shinbo has some similar tricks up his sleeve Sasami-san might also turn out to be a classic.