Earlier in my countdown when I introduced Ron Zacapa Centenario (23 Solero), I spoke of Ron Zacapa’s ‘House above the Clouds’ and the aging process known as Sistema Solera. It turns out that Ron Zacapa produces not just one outstanding luxury sipping rum, but two. The Ron Zacapa XO (25 Year Solero) is blended from solera aged stocks which range in age from 6 years to 25 years. This rum, like its slightly younger sibling, is aged in a mixture of solera aging barrels which include American Whisky casks, and Sherry and Pedro Ximenez wine barrels. However, the difference is in the finish, which is where, for the Ron Zacapa Xo (25 Year Solera), cognac casks are introduced into the aging regimen.
It is probably just a matter of preference, but for the record, every Judge (including myself), on my Judging Panel, showed a slight preference for the Cognac finished Ron Zacapa XO which arrives in the number 4 spot in the Rum Howler Top 30 Countdown of the Best Rums in the World.
# 4 – Zacapa XO (25 Year Solero) Rum
A rum full of complexity with almost perfect balance and smoothness. A delicious, sweet rum that had my taste buds absolutely reeling with delight.
The El Dorado 12 Year Old Special Reserve Rum is blended from aged stocks (the youngest being no less than 12 years old) from the original Wooden Enmore Coffey still, the original metal Diamond Coffey still, as well as from the ancient Port Mourant double wooden pot still which was used to produce ‘navy’ rum for the English Admiralty. All of the Demerara Rum produced by El Dorado is aged exclusively in American oak (bourbon barrels). Demerara Distillers Ltd. (DDL) has built a reputation for outstanding quality. Their use of old traditional stills in conjunction with modern stills and distilling techniques have helped them earn world-wide acclaim for their Luxury Cask Rums.
The rums of 
The Panamonte Reserva XXV is a new well aged Panamanian rum from PANAMONTE BRANDS. This is a molasses based rum produced from sugar cane grown and distilled in Las Cabras de Pese. Handcrafted by Master Blender, Francisco “Don Pancho” Fernandez Perez, this rum is very special, as every drop of the Panamonte Reserva XXV rum has been aged for a minimum of 25 years in used bourbon casks.
The Plantation Guatemala Gran Anejo is a Guatemalan rum produced from sugar cane syrup (rather than molasses) on a short column still. The rum is aged for a minimum of four years in bourbon casks in Guatemala after which it is transported from Guatemala to France by 
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