He supposedly has an above average arm and has impressed scouts with it. Cespedes was decent in the OF when he played LF instead of CF. He obviously lacked the range for CF, but he's got a very strong arm.
Cespedes and Alvarez put up similar numbers in their last seasons in Cuba, and again Cespedes was older. Alvarez needs to work on his plate discipline, but at least he makes a good amount of contact.
For a team lacking high-end outfield options, he could be a nice investment for us. He will require a multi-year deal, but the money shouldn't be too crazy.