La Corona oscuros have a "cooked" maduro wrapper - darkened by heating the wrapper leaves artificially, not letting them age as most maduros. The tipoff is that they will leave stains on your lips, tongue, fingers, etc. Naturally aged maduros are entirely different, having a more natural look, no stains, and that great maduro taste. Thankfully, only a handful of cigar makers cook their wrappers - and none of the big names like Fuente, Villazon, etc.