Matusalem does indeed have a good reputation, unfortunately it is undeserved. They are a very long way from truthful and forthcoming about their product. When the family left Cuba some of the relatives went to Miami and some to the Dominican Rep. The court battle between these two factions of the family contains a sworn statement detailing the recipe used for their Rum and it contains Macerated Prunes and Vanilla Beans. In short they are as guilty as any other manufacturer of using flavoring additives and then denying that they do.
How truthful their website is, is of course up to debate. However, they do have a pretty good reputation in the rum world, and their solera rums are some of my favorites. Matusalem labels their bottles of solera rum with the "average" age of the rum in the bottle, and so you theoretically have much older rum in the blend than is advertised. This just seems to be a more truthful and honest approach than most of the other rum producers who market solera-aged rums.