don't think i can answer this poll
they're different flavors, so i go to each for different reasons
not really a huge mickey d's fan unless i get a craving for the mustard & pickle goodness of their regular cheeseburgers (which can be eaten like white castle mini burgers). their fries are better than mos burger, but otherwise they're "meh".
mos burger's alright but it's extremely small, the fries are terrible, and for all the ranting and raving everyone does about the meat, it tasted pretty processed to me- though it mighta been my taste buds associating the chili sauce with chef boyardee (which it has some slight resemblance to).
I don't know that mos burger would even be the best in japan, that title probably goes to Kua 'Aina.
if i want a real burger i'll go to fuddrucker's or red robin.
ruby tuesday's, friday's, and chilli's have passable substitutes.
if i want the grease i became addicted to growing up on military bases across the world, i'll go to burger king (who also has good grilled chicken sandwiches, fries, and the texas double whopper).
if i want a similar grease at 3 or 4am i'll go to wataburger
A&W has alright burgers, but at least the fries are better than Mos burger.
jack in the box has a killer patty melt.
sonic, checker's, and in-n-out burger are not to be forgotten either.