The Natural line are completely UNLIKE the ACID line. In fact, I don't know WHY the fine folks at c-bid refer to it as the "ACID Natural line" because it has NO similarity in taste or manufacturing process as the ACID line does. (though they are made at the same factory in Nicaragua)
The Natural line is blended with a variety of tobaccos from some unlikely countries for cigars (ie. Turkey, Syria, China, etc.). There is even some tobacco in there that is traditionally used for pipes. The result is a mild smoke and inoffensive smoke and aroma (smells like someone's smoking a pipe). The Natural line comes in a variety of shapes, sizes and wrappers. Although almost all of the line is long-filler, I personally, like the "Dirt" and "Jucy Lucy" sizes (small, mixed filler smokes). Out of the other sizes, the "Green Hero", "White Rabbit", "China 5" and the new "Leche" are good. The "Egg" is a BIZARRE shape and it's like smoking a fist.
Hope that helps.