According to the search results, Harvey Specter, a character from the TV show "Suits," is known to drink Macallan 18, a single malt Scotch whisky. This is a high-end whisky that is aged for 18 years and has a rich, smooth flavor. In one of the episodes, Harvey is seen drinking a beer called "An Brain Blásta," which is described as sweet, bright, and lively. However, this beer is not related to Harveys usual drink of choice. It is also mentioned in one of the search results that if the bar didnt have anything over $100 a bottle, Harvey would get water. Overall, it can be concluded that Harvey Specters preferred drink is Macallan 18, a single malt Scotch whisky.