Years ago I would buy Zacapa but not now as I feel the quality has diminished and I would agree that it's overrated. Last time I tried it there was a weird artificial taste. I would also extend that to the Diplomatico Reserva Exclusiva; I picked up a bottle of that for my dad and was less than impressed.
As for El Dorado 15 and the 12, if sweetened rum is your thing then these are the way to go. They taste great and the age statements are bona fide; no crazy, ambiguous, opaque solera systems with El Dorado.
