perfect being almost raw in the middle, or even actually raw, but not cold.
i've had a decent one at kua aina and i heard the counter does it.
burgers on the edge wouldn't do it, it had to be well done. they're gone anyway. good riddance, i say. (i'm still mad about the $30 burger that was one of the worst burgers i've ever had.)
teddy's will accept a really really rare order, but when it comes out it's well done.
unlike some others, i like cheeseburger in paradise (have not eaten at cheeseburger waikiki, their sister store), but it was more of a medium rare.