American or "aromatic cedar" is extremely aromatic and penetrating. Ever pull a sweater out of a cedar chest and slip it on? Spanish cedar is a more mild and less penetrating scent. It is also less sappy than aromatic cedar. I have not had any personal experience with cigars aged in aromatic cedar, but I have read in various magazines that it will ruin a cigar in no time. Apparently they start tasting like the cedar smells, masking all other flavors and tastes that the cigar might have previously had.