A 1976 aluminum boat in our harbor frequently wins its division in the Newport-Bermuda, Vineyard, and Block Island races. (Continuing the tradition this past season as well.) The owner obviously sails well, but the Aage Nielsen design is not at fault either. There has been no apparent problem with paint adherance. Electrolysis is generally something to stay aware of - and ahead of - on an aluminum boat. Any scratches or paint damage left exposed , especially below the waterline, can lead to catastrophic leaks. One-off costs can be higher than for some other materials because the welding is trickier than steel, for example, and the more skilled workers command higher wages. Material costs can also be higher for aluminum. You don''t want the same stuff they use for screen doors! Unless you''re stamping out mass volumes of rowboats or skifffs or are doing your own welding, aluminum boats seem to start getting cost-effecttive in the over 35'' range. (The one at the head of this post is 43'' long.) The trade-off benefit is lighter weight, which makes, as noted above, for a faster boat.