There is no inherent advantage or disadvantage to monads. If the idea is most clearly expressed as a monad, use a monad. If the idea is most clearly expressed recursively, write it recursively (but perhaps wrap it in "return").
Perhaps the "inherent disadvantage" is that functions written in the monadic style must have different types compared with their conceptually similar non-monadic functions.. mapM :: Monad m => (a -> m b) -> [a] -> m [b] map :: (a -> b) -> [a] -> [b] filter :: (a -> Bool) -> [a] -> [a] filterM :: (Monad m) => (a -> m Bool) -> [a] -> m [a] foldl :: (a -> b -> a) -> a -> [b] -> a foldM :: (Monad m) => (a -> b -> m a) -> a -> [b] -> m a Some would say "but they're different functions!", others would say "close enough". I imagine this would be an absolute pain for library writers. Notice that we get Data.Map.map but no Data.Map.mapM - or perhaps there's some magical lifting combinator that I am not aware of? Ben.