There are some downsides, don’t get me wrong. For starters, Hugo hasn’t been around as long as Jekyll and, as a result, doesn’t not have as large of a community. Additionally, you may find a few holes in Hugo’s documentation–which is otherwise pretty great.
So what are you waiting for? Give Hugo a try. And, while you’re at it, check out the After Dark theme for a culture jamming take on content publishing in the new millennium.