The OP's question was not which medal is more prestigious, but which PERFORMANCE was more impressive.
Obviously, the Olympic Games will, in theory, benefit from better fields, with more athletes with greater amounts of focus, preparation and "nervous energy" (as Renato Canova would say).
Apart from that, however, I would agree that it should be considered that Kiprop, in his best form and not making any tactical blunders, was present in the Moscow Final, and that, Makh Daddy's Olympic Final performance was bizarre and certainly suspicious (he hasn't done squat since--compare this with Mo Farah's continual consistency). This gives a little extra weight to the Centrowitz's 2013 WC performance.
How consistent either athlete is, the rest of the time, is not really relevant when evaluating the merits of an individual performance, unless you really think an outlier breakthrough performance has less merit because the athlete is "throwing" performances against "the wall" and seeing "what sticks," and that an athlete who performs consistently is somehow, "probabilistically," disadvantaging himself for future triumphs (tell that to Mo Farah), or that breakthroughs in past world championships wear an athlete down in the long run (a year or years later)
An interesting point to ponder, abstractly, is that, the dominant countries of distance running--the East Africans: the Ethiopians and Kenyans--of course, face the same limits other countries do in sending athletes to Championships, and that, more so than other countries, the selection process doesn't necessarily result in the best athletes-- most suited and liable to perform well at a given championships--being sent. Thus, it is conceivable that, the qualifiers sent by Kenya to the Olympics one year might be weaker than those sent in a WC another year.